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Container soils and water in containers III

Posted by jdwhitaker 7TEX (My Page) on
Sat, Feb 24, 07 at 1:29

We've worn out two threads in less that two years since Al's original post. Let's keep the discussion going...

CONTAINER SOILS AND WATER IN CONTAINERS
Posted by tapla z5b-6a MI (My Page) on Sat, Mar 19, 05 at 15:57

The following is very long & will be too boring for some to wade through. Two years ago, some of my posts got people curious & they started to e-mail me about soil problems. The "Water Movement" article is an answer I gave in an e-mail. I saved it and adapted it for my bonsai club newsletter & it was subsequently picked up & used by a number of other clubs. I now give talks on container soils and the physics of water movement in containers to area clubs.
I think, as container gardeners, our first priority is to insure aeration for the life of the soil. Since aeration and drainage are inversely linked to soil particle size, it makes good sense to try to find a soil component with particles larger than peat and that will retain its structure for extended periods. Pine bark fits the bill nicely.

The following hits pretty hard against the futility of using a drainage layer in an attempt to improve drainage. It just doesn't work. All it does is reduce the soil available for root colonization. A wick will remove the saturated layer of soil. It works in reverse of the self-watering pots widely being discussed on this forum now. I have no experience with these growing containers, but understand the principle well.

There are potential problems with wick watering that can be alleviated with certain steps. Watch for yellowing leaves with these pots. If they begin to occur, you need to flush the soil well. It is the first sign of chloride damage.

One of the reasons I posted this is because of the number of soil questions I'm getting in my mail. It will be a convenient source for me to link to. I will soon be in the middle of repotting season & my time here will be reduced, unfortunately, for me. I really enjoy all the friends I've made on these forums. ;o)

Since there are many questions about soils appropriate for containers, I'll post by basic mix in case any would like to try it. It will follow the Water Movement info.

Water Movement in Soils

Consider this if you will:

Soil need fill only a few needs in plant culture. Anchorage - A place for roots to extend, securing the plant and preventing it from toppling. Nutrient Sink - It must retain sufficient nutrients to sustain plant systems. Gas Exchange - It must be sufficiently porous to allow air to the root system. And finally, Water - It must retain water enough in liquid and/or vapor form to sustain plants between waterings. Most plants could be grown without soil as long as we can provide air, nutrients, and water, (witness hydroponics). Here, I will concentrate primarily on the movement of water in soil(s).

There are two forces that cause water movement through soil - one is gravity, the other capillary action. Gravity needs little explanation, but for this writing I would like to note: Gravitational flow potential (GFP) is greater for water at the top of the pot than it is for water at the bottom of the pot. I'll return to that later. Capillarity is a function of the natural forces of adhesion and cohesion. Adhesion is water's tendency to stick to solid objects like soil particles and the sides of the pot. Cohesion is the tendency for water to stick to itself. Cohesion is why we often find water in droplet form - because cohesion is at times stronger than adhesion, waters bond to itself can be stronger than the bond to the object it might be in contact with; in this condition it forms a drop. Capillary action is in evidence when we dip a paper towel in water. The water will soak into the towel and rise several inches above the surface of the water. It will not drain back into the source. It will stop rising when the GFP equals the capillary attraction of the fibers in the paper.

There is, in every pot, what is called a "perched water table" (PWT). This is water that occupies a layer of soil that is always saturated & will not drain at the bottom of the pot. It can evaporate or be used by the plant, but physical forces will not allow it to drain. It is there because the capillary pull of the soil at some point will equal the GFP; therefore, the water does not drain, it is "perched". If we fill five cylinders of varying heights and diameters with the same soil mix and provide each cylinder with a drainage hole, the PWT will be exactly the same height in each container. This is the area of the pot where roots seldom penetrate & where root problems begin due to a lack of aeration. From this we can draw the conclusion that: Tall growing containers are a superior choice over squat containers when using the same soil mix. The reason: The level of the PWT will be the same in each container, with the taller container providing more usable, air holding soil above the PWT. Physiology dictates that plants must be able to take in air at the roots in order to complete transpiration and photosynthesis.

A given volume of large soil particles have less overall surface area in comparison to the same volume of small particles and therefore less overall adhesive attraction to water. So, in soils with large particles, GFP more readily overcomes capillary attraction. They drain better. We all know this, but the reason, often unclear, is that the PWT is lower in coarse soils than in fine soils. The key to good drainage is size and uniformity of soil particles. Large particles mixed with small particles will not improve drainage because the smaller particles fit between the large, increasing surface area which increases the capillary attraction and thus the water holding potential. Water and air cannot occupy the same space at the same time. Contrary to what some hold to be true, sand does not improve drainage. Pumice (aka lava rock), or one of the hi-fired clay products like Turface are good additives which help promote drainage and porosity because of their irregular shape.

Now to the main point: When we use a coarse drainage layer under our soil, it does not improve drainage. It does conserve on the volume of soil required to fill a pot and it makes the pot lighter. When we employ this exercise in an attempt to improve drainage, what we are actually doing is moving the level of the PWT higher in the pot. This reduces available soil for roots to colonize, reduces total usable pot space, and limits potential for beneficial gas exchange. Containers with uniform soil particle size from top of container to bottom will yield better drainage and have a lower PWT than containers with drainage layers. The coarser the drainage layer, the more detrimental to drainage it is because water is more (for lack of a better scientific word) reluctant to make the downward transition because the capillary pull of the soil above the drainage layer is stronger than the GFP. The reason for this is there is far more surface area in the soil for water to be attracted to than there is in the drainage layer.

I know this goes against what most have thought to be true, but the principle is scientifically sound, and experiments have shown it as so. Many nurserymen are now employing the pot-in-pot or the pot-in-trench method of growing to capitalize on the science.

If you discover you need to increase drainage, insert a wick into the pot & allow it to extend from the PWT to several inches below the bottom of the pot. This will successfully eliminate the PWT & give your plants much more soil to grow in as well as allow more, much needed air to the roots.

Uniform size particles of fir, hemlock or pine bark are excellent as the primary component of your soils. The lignin contained in bark keeps it rigid and the rigidity provides air-holding pockets in the root zone far longer than peat or compost mixes that rapidly break down to a soup-like consistency. Bark also contains suberin, a lipid sometimes referred to as natures preservative. Suberin is what slows the decomposition of bark-based soils. It contains highly varied hydrocarbon chains and the microorganisms that turn peat to soup have great difficulty cleaving these chains.

In simple terms: Plants that expire because of drainage problems either die of thirst because the roots have rotted and can no longer take up water, or they starve to death because they cannot obtain sufficient air at the root zone for the respiratory or photosynthetic processes.

To confirm the existence of the PWT and the effectiveness of using a wick to remove it, try this experiment: Fill a soft drink cup nearly full of garden soil. Add enough water to fill to the top, being sure all soil is saturated. Punch a drain hole in the bottom of the cup & allow to drain. When the drainage stops, insert a wick several inches up into the drain hole . Take note of how much additional water drains. This is water that occupied the PWT before being drained by the wick. A greatly simplified explanation of what occurs is: The wick "fools" the water into thinking the pot is deeper, so water begins to move downward seeking the "new" bottom of the pot, pulling the rest of the PWT along with it.

Having applied these principles in the culture of my containerized plants, both indoors and out, for many years, the methodology I have adopted has shown to be effective and of great benefit to them. I use many amendments when building my soils, but the basic building process starts with screened bark and perlite. Peat usually plays a very minor role in my container soils because it breaks down rapidly and when it does, it impedes drainage.

My Soil

I'll give two recipes. I usually make big batches.

3 parts pine bark fines
1 part sphagnum peat (not reed or sedge peat)
1-2 parts perlite
garden lime
controlled release fertilizer
micro-nutrient powder (substitute: small amount of good, composted manure

Big batch:

3 cu ft pine bark fines (1 big bag)
5 gallons peat
5 gallons perlite
1 cup lime (you can add more to small portion if needed)
2 cups CRF
1/2 cup micro-nutrient powder or 1 gal composted manure

Small batch:

3 gallons pine bark
1/2 gallon peat
1/2 gallon perlite
handful lime (careful)
1/4 cup CRF
1 tsp micro-nutrient powder or a dash of manure ;o)

I have seen advice that some highly organic soils are productive for up to 5 years. I disagree. Even if you were to substitute fir bark for pine bark in this recipe (and this recipe will far outlast any peat based soil) you should only expect a maximum of three years life before a repot is in order. Usually perennials, including trees (they're perennials too, you know ;o)) should be repotted more frequently to insure vigor closer to genetic potential. If a soil is desired that will retain structure for long periods, we need to look to inorganic amendments. Some examples are crushed granite, pea stone, coarse sand (no smaller than BB size in containers, please), Haydite, lava rock, Turface or Schultz soil conditioner.

I hope this starts a good exchange of ideas & opinions so we all can learn.

Al


Follow-Up Postings:

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RE: Container soils and water in containers III

Here's the link to the thread. Certainly worthy of a reading session, especially if you're just starting out, or have been having plant problems, or just want to experiment.

Here is a link that might be useful: Click here.....there will be a test afterwards ;-)


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RE: Container soils and water in containers III - The soilless in

Having read about Al's mix, it seems that the following applies to the soiless mix.

A.) Ingredients are larger to allow bigger pores between particles and better water drainage

B.) The Pine Bark and Peat have Cation Exchange capacities that will help to hold nutrients and make them available to plant roots

C.) Lime is used for Calcium, which helps to drive a lot of plant functions.

D.) Perlite provides little more than a long lasting open structured medium that promotes draining.

E.) Better drainage comes at the expense of more frequent watering, but this yields better plant growth.

Regarding the substitution of soiless mix materials, it would seem that three goals exist.

First, use a free-draining large particled medium that does not break down easily.

Second, use a medium that includes a high cation exchange capacity.

Third, fertigate regularly enough to prevent root dry out and death, but not waterlogging and death. The fertilizer in the water should not be overly strong or salty, but rather low doses of a complete fertilizer like kelp meal and fish emulsion with mineral additives to keep the Calcium to Magnesium ratio in recommend range.

Questions:
Q1. Expanded clay pellets, like used in hydroponics, have a high C.E.C. rating and hold small amounts of water. Would they be a good replacement for the peat moss?

Q2. Chipped corn cobs are sometimes used in container mixes. Would they work as another substitute in the Al's Mix?

Q3. With frequent watering, more nutrients are washed away. Could a tray be used to collect nutrient-containing water that could be used with a timer and pump to re-water the container every 12 to 48 hours?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Feb 28, 07 at 13:14

Anyone that knows the word "fertigate" has done some homework. ;o)

1) It depends on the size (and volume) used. Turface is calcined clay and is an ideal amendment/ingredient for container soils. I tend to use it in soils that require more stability - plantings that will go two or more grow seasons between repots. There are other products that may work as well as Turface, but I find it ideal for my purposes. It doesn't break the bank either.

Turface has excellent CEC. It has about 13 acres of surface area per pound of aggregate (that's per pound - and that's a whole lot of nutrient attachment sites) ;o). It's bulk density is very low, @ about .4-.5 g/cc and it has an internal porosity of about 45 - 50%. It's price is reasonable - I pay about $8.50 per 50 lbs.

I grow many plants in nothing but 100% Turface.

2) I suppose they would work short term, but they are largely cellulose & I would be concerned about rapid decomposition and water retention/aeration issues. Splendid in the garden though.

3) Recirculating fertigation systems are common greenhouse and hydroponic tools. Just remember that simply topping off the reservoir will create a situation where metal salts from fertilizers and irrigation water will become increasingly concentrated. This could impede water and nutrient uptake if the system is not flushed frequently.

Ideally, we would water until soil is nearly saturated. Wait a short time (10 minutes perhaps) & water again so that about 10-15% of the total volume of water applied drains from the container, carrying excess salts with it. This insures minimal water/fertilizer waste & an uncomplicated way to limit salt build-up in soils.

Al


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RE: Container soils and water in containers III

I have been wondering if using cedar bark fines instead of pine bark? The only reason being the town I live in, I haven't been able to locate pine bark fines. Almost all sources that could possibly carry it have been checked out. It seems the locals here prefer the cedar, as it keeps bugs away.


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RE: Container soils and water in containers III

Mix Modifications for Vegetables...,
If we were to set two extremes, ranging from a container of waterlogged clay to a container-less plant with roots suspended in air and misted with water, we could create both soil and soilless mixtures all day long that would be somewhere between the two extremes. I see the Al's basic mix as being good for many plants, but wonder about modifying the ratio and ingredients for different plant needs. The materials used to create the proper conditions depends on the plant species and variety, as well as the stage of growth.

When selecting a container mix, I see the following as the major criteria governing success.

> Room for root growth
> Drainage and aeration
> Moisture retention and availability
> Nutrient availability

The following link points to some other container mixes developed and used commercially.

Commercial or University Soil Mixes

I have seen that Walt Disney World uses a different system for their hanging gardens. This includes a wire frame basket lined with sphagnum peat liner, an internal water reservoir that lasts up to 7 days, potting soil mixed with peat, a water retention gel layer in the middle, and a special organic mat on the top of the basket into which the flowers are planted. This matting is a couple inches thick and not only slows soil drying, but also release nutrients. Maybe this system was developed to deal with both scorching heat and infrequent watering. Nothing here to suggest this method should be used as a replacement for well aerated mixes, just that methods may differ by region and conditions.

Regarding outdoor container gardening, I have not seen much literature. I have seen some attempts using 5 gallon buckets, EarthBoxes, and whiskey barrels. While these container vegetable gardens survived and produced, they did not look as optimal as raised bed grown vegetables. Here is a link to a 5 gallon bucket garden.

5 Gallon Bucket Garden

I raise most of my large vegetables in raised beds, but have a retiree who wants to garden in containers. Would the basic Al's Mix be good for whiskey 1/2 barrels, when growing tomatoes, bush squash, icebox melons, onions, and potatoes? Has anyone tried Al's Mix on vegetables, and are any modifications suggested to grow the plants listed? Also, with subsurface root structures from seed grown plants concentrated in the upper part of the container, there is concern over keeping the largest collection of roots from drying out in the upper 4 to 5 inches of surface of growing medium with a fast-draining mix. Would concentrating more water-holding materials in the upper part of a large container be worthwhile for plants with roots that do not like to dry out between watering in windy and hot outdoor environments?


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RE: Container soils and water in containers III

I see the Al's basic mix as being good for many plants, but wonder about modifying the ratio and ingredients for different plant needs.

An interesting choice of words. I would say the exact same thing, but I would replace 'plant needs' with 'grower needs'.

When it comes to plant needs this is pretty straight forward and I believe Al has the right idea. Growers (theoretically) can add unlimited amounts of water and nutrients to containers, but the one thing growers can't do is add oxygen to a growing medium. Nature has to do that. Yes, I realize hydrogen peroxide can be used to add oxygen, but...

As a result build a growing medium that allows for ample oxygen and have the grower compensate by increased labor in terms of watering and fertilizing.

I agree 100% with Al in that the aeration of the growing medium is of critical importance.

I, however, do not have the time/ability to attend to daily or twice daily waterings during the summer. If my plants depended upon me to do so, they would all die.

The end result is I prefer very large containers with a growing medium that retains lots of water to extend my watering interval.

Would I get better results if I could water more frequently?

I believe so.

But I can't and I have not yet gotten the drip irrigation system down pat with the various sized containers and plants with varying water needs so...

As Al has said repeatedly in the past, every choice in growing medium is about compromise.

There is what is best for a plant and there is what is best for the grower and the two are not always the same.


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RE: Container soils and water in containers III

Creister,
Aren't you in the Abilene area? It can be difficult to find pine bark this early in the year--but it should be everywhere soon. I know I often have some difficulty finding it in the Odessa area during the "off season", while pine bark is always abundant (and cheap)in Dallas. I'm often traveling down I-20...be happy to toss out a couple of bags on my way through if you need.

I'm not sure about the cedar--that mulch may be the actual wood and not just the bark. The bark is what has the high lignin content which makes it hold up well and not break down.

Jason


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Mar 1, 07 at 21:10

Creister - The common name "cedar" is used to describe various species in more than a half dozen genera I can quickly think of. Find the genus and species of the tree you are inquiring about, add bark after it, put quotes around it and add the words phytotoxic or allelopathic after it and you should find your info.
For example: "Thuja plicata bark" allelopathic or "Thuja plicata bark" phytotoxic.

Deep roots - I'm not sure if you're inviting comment in the first 3/4 of your post, or if you're sort of thinking aloud. I also noticed a few of the same things JaG mentioned. I would make the note that of the 4 things you mentioned as most important in selecting a container mix, only 2 actually are:
> Room for root growth ---- \ More an issue of container size.
> Drainage and aeration ---- Agree
> Moisture retention and availability ---- Agree
> Nutrient availability ---- Not too important - easily grower-supplied

To address the last paragraph; Lots of folks (me included) have grown veggies in some variation of the soil mix I often suggest and have been extremely happy with results. I have no need or want to see anyone adhere strictly to a recipe I supply. Think of it as a starting point & grow from there. I probably place far less emphasis on the actual ingredients that go into a soil. As long as they perform a needed function & are not toxic - I'm good with it.

Your idea: " ... with subsurface root structures from seed grown plants concentrated in the upper part of the container, there is concern over keeping the largest collection of roots from drying out in the upper 4 to 5 inches of surface of growing medium with a fast-draining mix." is something I'd like to comment on.

In reading this, it sounds like you may have grown in a highly water retentive mix in the past, which would tend to concentrate rootage above the PWT. If that is true, then a more open mix would have seen roots colonizing throughout the container. Roots will grow deep in well aerated soil (in situ or container soils) in search of water & nutrients. The more lignified and suberized roots near the surface are simply hydraulic conductors anyway & serve little function in absorption of water or nutrients.

If you're concerned about evapo-loss from the upper limits of containers - simply mulch to minimize the drying effect of wind & sun and water more.

Plantings that actually require daily watering will generally produce plants with better vitality than those that are able to go days between waterings. It has to do with root death in anaerobic conditions and subsequent regeneration when air porosity returns to favorable levels.

Al



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RE: Container soils and water in containers III

Thanks for the offer JD. I finally found some yesterday at, would you believe, HEB grocery store. The pieces were ground real fine as well. Good growing this year. Hope we don't get a warm April and May.


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RE: Container soils and water in containers III

That's good news Creister. HEB often has suprisingly good gardening items--I've bought a lot of whiskey barrel containers from them. You should be happy with a pine bark based soil. I can't believe I ever wasted money on those "name brand" potting soils.

Jason


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RE: Container soils and water in containers III

  • Posted by galcho z8 Northwest (My Page) on
    Sat, Mar 3, 07 at 8:53

Pine bark: should it be composted or fresh bark can be used?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Mar 3, 07 at 18:03

If unfertilized, plants growing in fresh bark will generally be smaller, show less chlorophyll and have lower levels of available N in leaf analysis than plants growing in aged bark. These differences would be caused by the tendency toward greater N immobilization in fresh bark and perhaps a slightly lower pH. It's correctable with supplemental N applications.

FWIW - Levels of phosphorus (P) are similar for fresh and aged bark, and probably don't need much supplementation. Available potassium (K), should be within the ideal range. Calcium (Ca) and magnesium (Mg) levels are similar (to each other), but lower than recommended. This isnt terribly important as we should be incorporating dolomitic lime into bark-based soils, which should correct the deficiency.

Short answer: Use either, but plan on more supplementation of N if you used uncomposted product.

Al


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RE: Container soils and water in containers III

  • Posted by galcho z8 Northwest (My Page) on
    Sat, Mar 3, 07 at 18:22

Just came from a store, they have bark that is combination or fir, hemlock and pine (medium). Will it work?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Mar 3, 07 at 22:51

I've used all of those types of bark with good results - no reason to think that they would not be a good choice collectively if particulate size is suitable and it's combined with other appropriate ingredients.

Al


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RE: Container soils and water in containers III

I have two more questions. Forgive me if they have been answered in other posts.

1.) Do I need to wet the mix before putting it into the container, similar to what one does with pro-mix and other soil mixes?

2.) I am going to use the mix in homemade earth boxes. Will this mix wick the water upward from the water resivor in the bottom of the pot?

Thanks,
Curt


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Mar 5, 07 at 13:30

1) Anytime peat or bark dries down to under about 30% moisture content, it becomes hydrophobic (water repellent - difficult to rewet), which can be an issue when watering from the top of the container. I always make sure my soils are a little moist when I mix them and when I build a planting.

2) Yes

Al


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RE: Container soils and water in containers III

"Has anyone tried Al's Mix on vegetables, and are any modifications suggested to grow the plants listed?"

I started using a variation of Al's recipe last year with very good results. I used more peat moss and this year I'm incorportating some Turface for the first time.

That's a real nice terraced setup you got there!


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RE: Container soils and water in containers III

Hello Al. Got a question about fertilizer. I bought osmocote 19-6-12. I bought the time release 8-9 month. They also had the 3-4 month. The 3-4 month would have been ok for my annuals. But Im doing perannuals also. So I thought the 8-9 would cover both. Im I ok? Thanks my freind. Mark


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Mar 14, 07 at 17:47

Yes, you're fine, Filix. The increased frequency of watering and the higher temperatures of of soil in containers (release of nutrients is also temperature dependant) speeds delivery over what it would be in in situ situations. I like the longer delivery formulas in containers, using regular additional supplemental applications of fish/seaweed emulsions and soluble fertilizers like MG.

Al


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RE: Container soils and water in containers III

Hi,

I've got maybe a dumb question that probably can't be answered very specifically - but having no shame , I'll go ahead and give it a try....

As I plan to use my container garden atop a table, I'm concerned with weight. Assuming I use the mix described (6 parts pine bark, 1 part peat, and 1 part perlite) and had drain holes and a wick to drain from the PWT, any "guestimates" on what the weight might be as compared to water of the same volume? For example, if I fill my container half-way full with water, might I conclude that my properly watered and drained container soil mix would be no heavier? I guess I could just do an experiment, but thought I'd check in here first. Would just like a general idea....

Thanks,
Anne


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Mar 16, 07 at 19:15

The bark-based soils I use weigh about 23 pounds per each 5 gallons or about 4.50 lbs per gallon when slightly moist and about 5.33 lbs per gallon at container capacity (saturated). Water weighs in at 8.33 lbs per gallon, so water would be very close to 1.50 x the weight of saturated soil.

Don't forget the added weight of accumulating biomass as plants grow .....

Al


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RE: Container soils and water in containers III

Hi Al,

Thanks! That's very helpful.

Anne


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RE: Container soils and water in containers III

Hello Again Al. Should I add more lime to my mix, since I'm useing non composted pine bark. Or should I just add more lime when a plant calls for a higher ph? Like for instance, I will grow some hyacinth bean vine. They like nutral or higher I'm told. Or Canna like a nutral or lower. Thanks again for all your help. Out of all the threads I have read I have learned the most with this one. Filix


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RE: Container soils and water in containers III

Hi Al,

If you'll bear with me again ....

I'm still a bit confused on things and have had a hard time putting together some of my thoughts on the subject. Somewhere "up above," I think you mentioned that top watering the bark mix could be problematic if things had dried out totally (or close to). To me, this sort of seemed to imply that you might need to bottom water.

I was wondering just what might happen with your soil mix if you had a wick from the top surface of the soil, out the bottom, and into a bucket or saucer of water. Say you top watered and saturated the container. The excess water would wick out the bottom, but with the end of the wick in a saucer or bucket of water, would there be enough capillary action in the soil mix to draw some of the water back up to the top surface of the soil, keeping the soil "damp" but not saturated? In other words - good drainage with air spaces but not still not drying out. If the wick goes below the end of the PWT, I would assume that the PWT would no longer be "flooded," but would still hold some water. I might be describing something like a capillary mat using the wick(s), but don't know if it would work in your container mix. Hope I may SOME sense .
Anne


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Mar 18, 07 at 21:00

Filix - I'm not sure I understood your question, but almost all container soils will be deficient in Ca w/o supplementation, so you should always have a way to supply it. Bark based soils will be high in P and likely have sufficient K. Mg and S will also need to be supplemented. The most likely micro-nutrient deficiencies would likely be B and/or Zn. I would look for a complete fertilizer that has the minors included or supplement your fertilizer program with one of several good sources of micro-nutrients.

Anne - I think I "got" your question. At somewhere around 30 - 35% moisture content, both bark and peat begin holding water so tightly it becomes unavailable to plants. They also become hydrophobic (water repellent) at this level of moisture. You needn't extend the wick all the way to the top to take advantage of capillary (wick) watering in the soils I suggest. If the wick extends an inch or two into soil through a drain hole, that is sufficient. I've often set containers newly planted with completely dry soil in a pan of water to initially hydrate the soil. Within an hour or so, even containers that are >16 inches deep will show the surface soil to be moist.

Regular watering via a wick does reduce compaction of soils, but it also increases the likelihood of metal salts/carbonate build-up from fertilizers and irrigation water unless you regularly flush the soil.

Al


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RE: Container soils and water in containers III

Southern pine bark and Northern softwoods are usually employed to increase bulk density and increase air space. In addition, bark will slightly reduce the water holding capacity of the mix, and there is some evidence that bark imparts some disease resistance. Bark is usually described as aged bark or as composted bark. Insufficient aging or composting could result in excessive heating of the mix or draw excessive nitrogen, but these materials are usually tested thoroughly before use by reputible companies. The fertilizer level of these mixes are usually amended with additional nitrogen. I do not use bark mixes for seed germination, but find them attractive for potting-on in several cases. "This information about Insufficient aging or composting resulting in excessive heating of the mix or drawing excessive nitrogen made me a little nervous.Because my pine bark is pretty fresh." Is this why you use a high nitrogen controled release fert? Filix


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RE: Container soils and water in containers III

Thanks Al!

On the metal salts/carbonate build up issue... Is this a by-product of a time release fertilizer that the plant will never use up assuming that the plants might just take in the other components of the formula? It would seem that if you were more or less "recycling" the irrigation water via the wick method or otherwise (some have mentioned using a pump), the "good part" of the fertilizer mix that would normally be lost in a fast drain situation would be returned to the soil so you wouldn't need to fertilize so often - hence less harmful build-ups - or at least less frequent flushing required. What if the irrigation water was something like a dilute compost or fish emulsion tea? Would there be the same build-up of harmful metal salts, etc.?

I guess I'm trying to imagine a way to have the soil more or less "breathe" moisture once it's irrigated or "dosed." Sort of "exhales" into the outside resevoir through the loose soil and drain wick, but then "inhales" again via the wick until the water in the resevoir reaches such a level that its time for a new "dosing."

I just have a "passing aquaintance" with Eartboxes, so maybe this is the same general idea - not sure. Just sort of wondering how it all might work with your particular lightweight mix and how the type of fertilizer would affect the flushing requirements.

Anne


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RE: Container soils and water in containers III

Never mind that last question. I read back through the thread and got my answer. It was kind of a dumb question. My plants are growing great! Filix


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RE: Container soils and water in containers III

FROM AL: I like the longer delivery formulas in containers, using regular additional supplemental applications of fish/seaweed emulsions and soluble fertilizers like MG.

1. I don't recall seeing a longer vs shorter formula, I always use a fish emulsion so I would like to use a forumla where it would be acceptable for growing. Or would it be okay to add to either formula.

2. If top watering how long will the 3-4 month CFR acutally last, wouldn't contstant watering cause to wash away sooner?


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RE: Container soils and water in containers III

Constant watering doesn't seem to break down the controlled release fertilizers so much as extreme heat. I like to use a conservative amount of the CRF because of this--the plants don't get over-fertilized in 100 degree heat when the fertilizer would be at its peak release rate, while the plants growth slows down. This means less than adequate fertilzer during peak growth in the spring and fall, which is when I use additional soluble fertilizer. The release rate doesn't increase too terribly much in Texas heat, and probably wouldn't be much of a concern at all in Mass.

You could certainly fertilize with only soluble fertilizers if thats your wish. The CRF's are more of a convenience and a way to ensure that the plants are never without some nutrients (you can't fertilize with solubles if it rains for a week straight). I have seen a 5-1-1 fish fertilzer in slow release pelleted form recently--that might allow you to have your cake and eat it too.

Jason


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RE: Container soils and water in containers III

Ahh slow release fish fertilizer in pelleted form, did you notice who is marketing that product. BTW I wasn't trying to imply I desired only soluble just wanted to be able to use fish emulsion with Al's formula in addition to CRF. Thanks for your info I appreciate it.


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RE: Container soils and water in containers III

The pelleted fish fertilizer was the Alaska brand. I've seen it at all the typical "big box" places here in TX, and it's certainly available online. The formulation I saw was actually 8-5-1 and includes fish meal and fish bone meal. They apparently make several other formulations, some with other additives such as feather meal and alfalfa meal. I'm not sure about the release rate on these--probably very much tied to environmental conditions as with most organic fertilizers.

Here is a link that might be useful: Fish fertilizer


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RE: Container soils and water in containers III

  • Posted by jonib Zone 3 (My Page) on
    Thu, Mar 29, 07 at 14:18

AL,
I can't thank you enough for the info on planting in containers. I am kind of new to all of this. I tried growing in pots a couple of years ago and failed. I am now learning more why it failed. I want to try again but this time I am learning more before I get deeper into this. Thanks to you I am learning so much on some of the most important parts, the right soil etc. I can't plant outside because of the kind of soil and wild animals. So I am planning on a greenhouse made out of a room in my house with growing lights. I am going to try through the winter too.
Thanks again :)
Joni


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Mar 29, 07 at 18:59

Such kind words. Thanks, Joni. ;o)

Rich M - All the fish, seaweed, and other organic fertilizer products will be slow release as they need to be broken down by microorganisms before they are in a form that plants can absorb. This can be something of a disadvantage when m/o populations are low or activity is reduced due to things wet conditions, unfavorable pH or high salt levels (affecting m/o populations).

Below, I'll provide a link to some of the slow, pelletized organic fertilizers I use. Some are pretty inexpensive & contain most of the elements (including the minors) that plants need for good vitality. For any that are looking for a no N fertilizer, you'll also find the "hard to find" 0-10-10 on the page.

Al

Here is a link that might be useful: If you click me, I'll show you what Al's talking about ;o)


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RE: Container soils and water in containers III

Man! Making enough potting mix to fill four half wiskey barrels was some work! My back is sore. I can see why some might use a cement mixer. Filix


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RE: Container soils and water in containers III

Hi Al,

As I've mentioned in other posts, I'm basically doing a tabletop salad garden using a kid's wading pool. It won't have any bottom drain holes, but might have outlets along the bottom edge near the floor of the pool. The floor of the pool has sort of a depression around the perimeter and I was thinking about laying a wick in this "groove." The end of the wick would be directed away from the pool in a pipe nipple extending beyond the edge of the table and then hang down below the level of the pool floor. Depending on the situation, the wick could be used for bottom watering or draining. My question is - what sort of material would you use for a wick in this situation? I'm sort of picturing a 1/2" or so diameter cotton "rope" you might find in fabric or upholstery shops but don't know if this would be the best.

Thanks!
Anne


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Mar 31, 07 at 23:34

Well, it needn't be anything too special if you intend to use it to drain the PWT, but if you intend to use it as an aid to water uptake, it should be absorbent enough to "lift" water from your reservoir to the bottom of the soil in the container.

Man made chamois of 100% rayon is excellent, but it is a natural product, derived from cellulose & will need occasional replacement.

Al


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RE: Container soils and water in containers III

Thanks Al!

Anne


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Tomatoes

I am planning on growing 16 heirloom tomato plants this year in 4 20" cubic containers made out of styrofoam as first suggested by Leopold Klein who wrote the book "100 lbs of Tomatoes Out of an Inexpensive Foam Box (1988)." There are 4 plants per box. He used the following formula:
5 40lb bags of ordinary topsoil
1 cu.ft. of peat moss
1 cup of pulverised limestone
A few handfuls of generic 5-10-5

I would like to use a formula based on Al's but with some added specific ingredients that I already have:
3 cu ft pine bark fines
5 gallons peat
5 gallons perlite
1 cup Hi-Cal lime
1 cup Nutrients Plus Super "8" 5-8-5
1/2 cup Planters II Trace Mineral
2 cups Numus Concentrate 1.5-1.2-1.2 (already have it, but probably unnecessary?)
?? cups Soilmaster Red

Has anyone tried growing tomatoes this densly? It seems that it is even more dense than the square foot gardening, but I haven't read that book. Thanks for your recommendations on the soil mixture.


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RE: Container soils and water in containers III

stongml,

I've grown heirloom tomatoes for several years now. They've all been indeterminate and can get HUGE. I've had plants spreading laterally on a trellis at least 5' and growing 7' tall (when they sort of flop back down on the trellising line and continue growing in another direction).

I've found that 20" between plants is a bit too close for comfort without extensive pruning - and I can't imagine 4 in that space. I suppose that the plants would grow in the mix (although I really can't speak to that), but unless they were severely pruned and directed upwards somehow, you'll need to have a system directing the above ground parts of the plant outward from the container.

Don't want to discourage you - maybe it'll work great. I'm just trying to imagine where the bulk of the plants will end up.....

Sort of off topic - but what varieties are you planting?

Anne


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RE: Container soils and water in containers III

(I'm planting Aussie, Black Cherry, Black Krim, Suddath's Brandywine, Dagma's Perfection, Flamme, Green Zebra, Kellogg's Breakfast, Paragon Livingston, Better Boy)
I will also be using automatic watering twice a day so that is not a concern with the speed of soil drainage.


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RE: Container soils and water in containers III

Im planting many roses in containers this year so this is a very interesting topic to me.

My current technique is to use about a 15 inch top diameter plastic container with several inch holes at the bottom. I plant dormant bare root roses using Miracle Grow potting mix and mixing in a couple of tablespoons of SoilMoist crystals. I put a paper towel at the bottom of the pot before adding the soil. I have planted five roses already this year using this method and have been growing them in a bathtub that is under a couple skylights. After the first few weeks I added a couple grow lights. After about a month, I have about 20 buds about to open on one of the roses and the other roses are looking good too. I plan to put them outside sometime in the next month or so. I am watering them every four or five days with about a gallon of water each with about tbsp. of Miracle Grow for Roses per gallon.

That being said

How do the SoilMoist crystals effect the soil with regards to the ideas presented in this thread?

Would these roses benefit from putting a wick up through the holes in the container since they are already planted?

What type of wick should I use and should I use only one wick per container?

I read somewhere that using a paper towel at the bottom of the pot to keep the fresh soil from leaking out was a good idea. I did this, and wonder if it was indeed a good idea?

I have sandy soil in the yard. If I later decide to dig a hole in the sandy soil and put the entire pot in the ground, would this be bad or would it be good based on the pot-in-trench technique?

Any other suggestions?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 4, 07 at 18:05

How do the SoilMoist crystals effect the soil with regards to the ideas presented in this thread?

Some of the "extra-absorbent" characteristics mentioned by manufacturers of polymers are exaggerated, & as bio-degradation occurs these polymers actually reverse their effect and hold moisture so tightly it is unavailable to plants. Soils can usually be designed so forest products (bark), peat, and other organic media components that adequately hold moisture can be used with no ill effects. These products, even in containers, provide the plant(s) some nutrient value & fodder for the micro-organisms that polymers inhibit. Some degraded polymer components even have some of the same effects on mammals as female hormones, which can affect mammalian fertility and potency.

I have a jar of the product on the shelf I've had for years & never use. I tend to the opinion that it is probably useful for those that can't or won't water as often as a particular planting "prefers", but of course, that remains a personal decision.

Would these roses benefit from putting a wick up through the holes in the container since they are already planted?

If there is a saturated layer of soil that remains wet for more than a day, the answer is "Yes".

What type of wick should I use and should I use only one wick per container?

You can use anything you prefer that will move water through a combination of gravity & capillarity to drain containers. When using wicks to water, the wick needs to be capable of "lifting" water from the source to the soil in the bottom of the container. I use 100% rayon, man made chamois & replace them as required (they're a cellulose product & the same microorganisms that "eat" bark and peat will eventually break down the rayon wick).

The only advantage to using two wicks would lie in the fact that there would be a second, back-up wick if one is dislodged accidentally. The extra water in the PWT would drain a little quicker with two, but the plants wont mind if it happens to take 30 minutes instead of 15. ;o)

I read somewhere that using a paper towel at the bottom of the pot to keep the fresh soil from leaking out was a good idea. I did this, and wonder if it was indeed a good idea?

I've read that lots of people use coffee filters & pieces of old pantyhose too. Paper is largely cellulose (see above). I suppose it works, at least temporarily, but a little used insect screen (or new - it's really inexpensive) would be a better choice. There's even a kind of needlepoint plastic mesh that comes in 9 x 12 sheets at hobby stores that has larger openings than insect screening & does a stellar job.

I have sandy soil in the yard. If I later decide to dig a hole in the sandy soil and put the entire pot in the ground, would this be bad or would it be good based on the pot-in-trench technique?

Essentially, you'll be employing the earth as a giant wick and eliminating any perched water issues. There will also be the benefit of the earth's lower temperatures reducing container soil temperatures and moderating the wide temperature variance you find in container culture. You'll find this to be a good thing.

Just pay attention to the immediate need for more frequent irrigation as soon as you bury the container.

Al


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RE: Container soils and water in containers III

Al,

Thank you for the excellent answers and quick response! Your answers got me thinking and I came up with some more questions

What is the best way to determine if the saturated layer of soil remains wet for more than a day? As I understand it, its toward the bottom of the pot

How should I water and determine when the plants need water?

I have an acre lot that has many very large trees. Sunlight is limited and tree roots will eventually compete with the roses. I also live in zone 4 and most of the roses that I want to grow need extensive winter protection in my area. I am also considering selling my house in the near future, for one reason, to buy more property that is better suited for growing these roses. Planting the roses in containers is of particular interesting to me because:

- I can move the containers to protect the roses from cold and/or give them more sun.
- I dont have to worry about tree roots.
- I can conveniently take the roses in containers with me if I move.

Based on the above, it occurs to me that burying the containers in certain situations might give me the "best of both worlds". I could protect the roses from tree roots and move or transplant the roses while they remain in the pot and the roots remain undisturbed. I also wouldnt have to worry about issues with the surrounding soil. For instance, I could plant a rose next to a blueberry bush without having to worry about soil PH issues. I dont see this sort of thing done much so Im wondering if this another one of my crazy ideas ;-)

As for the "more frequent irrigation", perhaps the SoilMoist polymer might help with that temporarily Do I need to do anything special to make sure that there is a good connection between the soil in the pot and the ground under the pot? Could the wick continue to serve a purpose if put the end of it into the ground beneath the pot?

I hadn't heard of the degraded polymer's effects on mammals... That sounds pretty bad!

Im also considering a winterizing technique that I read about in which the pots are placed on their sides close together and then covered with a tarp folded over with straw in the middle. It seems that this would prevent water from getting to the dormant plants Should I worry about water or wicks or anything like that in this situation?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Apr 5, 07 at 17:37

What is the best way to determine if the saturated layer of soil remains wet for more than a day?

You can push a toothpick up through the drain hole where it will be quite effective as a "temporary test wick". If water drains out, there is perched water. Also: If feasible, you can drill a hole in the bottom of the container at the side. If you tilt the container, with the perimeter hole at the lowest point and water drains from the container, there is perched water. If you need an explanation for why this works, let me know.

How should I water and determine when the plants need water?

Best way to water containers: Moisten with enough water to soak in well, but not enough so it flows from drain hole. A few minutes later, water again so about 10-15% of the total water you applied appears at drain hole. These are going to be estimates, of course, but this watering habit insures accumulating salts are flushed from the soil and a minimum of nutrients washed out with the excess water.

You can determine the need to water in a number of ways. Lift the container to check its heft. You'll soon come to learn its water content by weight.

You can also sharpen a pencil-size dowel & insert it into the deeper part of the container. If it comes out damp & cool, your container likely does not need water at that time. You'll need to decide though, if it will have adequate moisture until the next opportunity to water.

You can lift the container & feel or examine the soil at the drain hole. If it's wet, you probably don't need to water.

Based on the above, it occurs to me that burying the containers in certain situations might give me the "best of both worlds". I could protect the roses from tree roots and move or transplant the roses while they remain in the pot and the roots remain undisturbed. I also wouldnt have to worry about issues with the surrounding soil. For instance, I could plant a rose next to a blueberry bush without having to worry about soil PH issues. I dont see this sort of thing done much so Im wondering if this another one of my crazy ideas ;-)

Not crazy at all, but that's been covered immediately above. The rose roots will "run" through drain holes, you'll have no perched water to be worried about and the reduction in temp & its fluctuation would be a + for added vitality.

Do I need to do anything special to make sure that there is a good connection between the soil in the pot and the ground under the pot?

No, not if at least partially buried.

Could the wick continue to serve a purpose if put the end of it into the ground beneath the pot?

No, not if partially buried.

Im also considering a winterizing technique that I read about in which the pots are placed on their sides close together and then covered with a tarp folded over with straw in the middle. It seems that this would prevent water from getting to the dormant plants Should I worry about water or wicks or anything like that in this situation?

Probably not, but you will need SOME air circulation to prevent fungal issues and you'll need to be sure that heat build up from sun exposure isn't an issue as temps warm in spring. Nurserymen in your zone often water well & then pack hoop/poly houses full of material & forget about them until spring, except to vent the houses on warm or sunny days to prevent heat build-up.

I overwintered >100 containers in my unheated garage with no additional protection. I only watered once, by throwing a shovel of snow on each plant, & all survived (again), so with you reducing evaporation with the tarp, and the condensation that will naturally form on the underside of the tarp, you'll be fine.

Pay very close attention to how you expose the plants to light in spring. You will need to begin sun exposure tentatively with plants that have over-wintered in the darkness of the tarp's protection.

Al


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RE: Container soils and water in containers III

If you need an explanation for why this works, let me know.
Al I would like to know. I noticed this when I bring my pots in from the cold frame and they tilt a little. If the pot stays level, nothing comes out.

Do some plants like a pwt? Or is it better to wick it all out so the roots have more room?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Apr 6, 07 at 21:18

Bonsai practitioners have long taken advantage of this phenomenon by tipping their pots in times of prolonged rain so they hold less perched water. I'll offer an example to show how it works:

Imagine a cellulose sponge (cuboid) thats about 4 x 6 x 1. If you put it in a pan of water until it's saturated, then lift it straight up, keeping it flat and its longest dimension horizontal. A few drops of water will drain from it, but no more. The reason is, the sponge will support a PWT that is higher than the sponge is tall (at this point, 1"). For this example, let's say the PWT height is 2". Holding the sponge by the tips now, change its position so the longest dimension is vertical. Since the sponge will only support a 2" PWT, the water in the top 4" of sponge immediately moves down and drains from the sponge. By changing the orientation of the sponge, you have removed 2/3 of the perched water. Now, tilt the sponge to that 2 of the corners are at the highest and lowest points. About 1/2 the remaining perched water (below the 2" PWT line) will drain, simply because there is less sponge material to hold water below that 2" (always horizontal) level of perched water. By tilting the sponge, you've created an inverted 3-D triangle (formed by the two sides of the sponge & the PWT line) from a cuboid. You can see that the cuboid is capable of holding more water than the inverted 3-D triangle, so the additional water must drain.

In tilted containers, there is simply less soil below the PWT level, so additional water drains.

********************************************************************** ****

No plants "like" a PWT, but many tolerate it to varying degrees. We "think" plants are fine with a saturated layer of soil, but in fact, the finest roots begin to die very quickly after they are deprived of O2. It takes longer for the older roots to be so affected, so they often remain viable after a portion of the fine, water and nutrient-absorbing roots are dead. When air eventually returns to the soil, the regeneration of fine rootage begins. It takes either stored energy or diverted photosynthate to rebuild roots, so this cycle is stressful to plants & diverts energy that could be used to increase biomass (flowers, fruit, foliage, stems and branches) or could be stored for later use.

Except in the case of a few plants (like bog dwellers) it is always better to grow under cultural conditions where no PWT is present, as long as you are able & willing to keep up with irrigation requirements.

Al


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RE: Container Soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Apr 6, 07 at 21:31

Pardon me please - No plants "like" a PWT should have read No plants "like" a PWT, except in the case of a few plants (like bog dwellers)...

Al


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RE: Container soils and water in containers III

I have a few more questions. I mixed my mix according to the reciepe from Al, and put it into some homemade self watering containers, similar to the earthboxes. It seems that every 2 or 3 the tomato plants in them need to be watered from the top. I did wet the mix before I planted or added water to the resivor in the bottom of the pot.
The mix is moist, but not overly wet as far as I can dig down into it. About like a sponge or wash rag that has been squeezed out.

Question 1.) Have I over saturated the pine bark and peat where it is holding the water too tightly and the plants are unable to absorb it? If so, how do I correct it?

2.) Earlier in the post, Al said if the peat and pine bark are 30-35% saturated, they will hold the water too tightly for the plants to use. What if they are saturated to a higher percentage, will the still hold the water? I would guess yes, but want to be sure.

3.) Could this just be an adjustment for the plants, as they have only been potted for about a week?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Apr 9, 07 at 17:09

Are you having some kind of plant problem? Damp, but not wet is perfect.

When peat and pine bark get below the 30-35% saturation point, their attraction to water is greater than the plant's, so plants cannot extract the water from soils that are this dry.

Soils that are at container capacity (100% saturated) will always have water available for plant uptake, but the process also requires air in the root zone.

You didn't say what the problem is, but plants are likely adjusting, yes, as they get their feet under them.

Not exactly sure I answered your questions, as I'm a little unsure of what you were asking.

Al


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RE: Container soils and water in containers III

The problem is that the plants want to slowly wilt over the two to three days after watering from the top. I am concerned that the mix is not wicking enough water up to keep sufficient water for the plants. You did clear up the 30-35% saturation. I thought it was just the opposite of what you said. Maybe I didn't wet the soil mix enough for it to wick enough moisture up from the resivor?


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RE: Container soils and water in containers III

Al,

I spotted this post and thought I'd ask you a question.
One of my Hoyas (Muliflora) has been blasting its buds (they turn yellow and fall off). This is a water loving hoya so I've been watering it much more than my others, which I figured might be the problem (overwatering).

Anywawy, I recently bought some wicks, and decided to try one on this hoya so that I get the watering right. However, I was told that I'm using it wrong because I don't put the wick through the bottom of the plant.
This is how I do it:

I followed the directions on the package (which also had a diagram that I precisely followed). The directions said to insert the plastic end of the string (looks like a piece of white sneaker shoelace, but it's not actually cotton of course) into the soil midway via the top of the soil, and put the other end into a cup of water that's lower than the soil level. It also said to water the string thoroughly first, which I did (I drenched it). I did this on Sunday, and the wick is still wet. Not only that, but I had to refill the cup of water yesterday, because it already drank about half of it. So it's definitely drinking.

I'd love to find out if it makes a difference whether you bottom wick or top wick. Should I switch to wicking from the bottom?

In case I didn't explain the method I used in a clear way, I found a site with a picture of a similar wick, and it shows the diagram and also a plant that's using the system. I'll attach the link to the picture.

Thanks so much for any help,
Gabi

Here is a link that might be useful: Top wicking system


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RE: Container soils and water in containers III

Double potting to reduce waterlogging: I decided to do this with certain soft-leaved plants and things which enjoy a cool root run this year. Is peat the best thing to use in the insulating/absorbing outer layer, or are there other options?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 11, 07 at 0:18

Creister - not sure what you have going on. I know that when I pot plants, even in containers that are 20" deep, after an hour or two sitting in a shallow pan of water, the soil is damp all the way to the top. Even extremely dry soils will eventually absorb enough water to moisten them via capillarity. If you're not getting enough water to your plants, you really do need to figure out something remedial.

Gabi - I don't think it matters, as long as both/either method(s) are getting the entire volume of soil moistened. I think there would be more evaporative loss if you wick from the top, so salts would build up, particularly in the upper part of the container, faster. Make sure that you regularly flush the container when wick-watering. Water well & allow salts to go into solution - then water again - copiously. This will carry salts out the drainage hole.

Kiwi - Turface, Espoma Soil Perfector, pumice, coarse sand would all be viable options too. The first three would also offer some additional air flow through the media & increase evaporative cooling.

Al


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RE: Container soils and Water in Containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 11, 07 at 0:23

Kiwi - I just noticed that you're from Japan. You may also have access to akadama there, which would be an excellent soil in itself in some cases, or an excellent amendment. It would also be very suitable as the media in the cache pot you'll be using.

Al


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RE: Container soils and water in containers III

Thanks Al,

I appreciate your quick response. Just one question. Because of the salt build-up, do you suggest I take a break from the top water-wicking every once in a while and then give a thorough top watering to flush the salts out? I'm pretty sure that's what you meant but I just want to make sure...

Thanks,
Gabi


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 11, 07 at 15:05

Yes - I think that's a good idea. Water thoroughly & then return a half hour later & water thoroughly again to flush soil. Your soil should be free draining enough so you can do this without risking an extended period of soggy soil. If it's not, consider changing your soil to one with better drainage/aeration.

Al


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RE: Container soils and water in containers III

Thanks Al. Yes, my soil has great drainage (mixure of peat moss, perlite, and cinder). Almost TOO MUCH aeration! When I water it, I think I'll have a hard time watering it without it directly flushing out...but I'll just water slow to allow it to sit for 30 minutes before the second watering where I flush it out. Thanks so much for your excellent advice. Much appreciated.

Gabi


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RE: Container soils and water in containers III

hi
i am new to GW,i wanted to find out can i use Al's mix in hanging baskets,i am planning to grow bareroot strawberries and i am planning to hang the basket on my south facing patio and do i need to add soil moist crystals to the mix,i am afraid the soil will dry out very fast.
thank you soo much for any help
Samira


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Apr 13, 07 at 17:01

I use the mix for a number of full-sun hanging containers (not cocoa fiber lined baskets, though) each year with no trouble here in zone 6a, but I water daily. You'll find that there is a trade off for growing in a well-aerated mix, and that is the need to water more frequently. Generally speaking tho, you should see a noticeable difference in plant vitality when you grow in a well aerated mix (all other cultural conditions being equal).

If you'll be growing in the fiber-lined baskets, you'll be able to use a mix that holds more water than the soil mix recipe I offered for containers. Because they dry quickly, air also returns to the soils quickly, making a soil that may not be the best choice in a container appropriate for use in a fiber-lined basket.

Whether the polymer amendment is appropriate in the basket you'll be growing in depends on too many variables to give a definitive answer, but I think it would be useful in a high % of fiber-lined baskets.

Al


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RE: Container soils and water in containers III

Akadama (granulated clay): yes, I do use this. Ranges from grit size to marble size. It's wonderful stuff for things like potted azaleas. However, it does eventually break down to a fine clay soil.

Thanks for your recommendations, I am sure I can find pumice here too.


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RE: Container soils and water in containers III

Advice on a large scale planting: I have to fill 17 whiskey barrel planters with new soil for our village. We will be planting perennials and annuals in the barrels, which will be in full sun on Main Street.

1. Would the pine bark mix suffice? I ask because it looks like two waterings are needed with 30 minutes between the two waterings; the village employees probably will not be able to do this.

2. In this application, considering the planters will be tended by village employees, would the water gel crystals be more useful or harmful?

3. If we added fresh soil to the barrels this year, would it really last for 3 years before needing to be replaced, assuming we would mix in fresh CRF and manure each year?

Thank you very much for any advice.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Apr 15, 07 at 23:59

I don't understand the first question, which also leaves me unable to answer the second because they are tied.

You may get three years out of a bark-based soil if you refresh it each year with some additional bark & possibly some perlite, but there will also be some substantial structural issues as components break down. Please - skip the manure and any thought of compost - especially if you "need" these plantings to perform over the long term w/o changing soils yearly.

Al


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RE: Container soils and water in containers III

The question is, what soil mix would you recommend for whiskey barrel plantings of perennials and annuals, located on Main St. and tended by village employees? I mention who they will be tended by, because the village workers do many other tasks, and maintaining planters will not be a huge priority for them.

I wondered if the pine bark soil mix recipe in the first message on this thread might allow us to get 2 or possibly 3 years out of the soil, to avoid having to replace soil in all 17 planters every year (about 4 cubic feet/planter). It sounds like you are saying that might be possible, if we add bark and perlite to maintain good soil structure. If we can't add compost/manure, I assume we will also need to mix in additional slow release fertilizer each year.

Does this sound like an intelligent plan, or do you have a better idea? Thank you again for your help.


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RE: Container soils and water in containers III

Newbie here, looking for advice. If only I had read this thread before planting...

I am concerned about my potted vegetable plants (tomatoes, cukes, strawberries). The soil I used (Scotchman's Choice Potting Mix) is not at all like Al's mix. It's very fine and looks to me like mostly clay, a little sand, and a little bit of wood chips. The density of this soil has concerned me from the beginning. I've used it in four large containers (1/2 whiskey barrel w/liner, and other 20" pots). After watering it quickly forms a dry, rock-hard top crust (nearly impenetrable!), but when I finally wedge the moisture-meeter down, it's regestering the soil below as saturated (from 2-8" below the surface). And the saturation level has not changed in nearly two weeks! Needless to say, this has alarmed me...and so this is how I came to this very informative thread. At this stage of the game, I can't bear to dismantle the large containers and start from scratch. (Next season, yes.) My question is, is there anything I can do to better the situation? Wicking will only be possible if I drill a hole in the sides of the containers (as they are too large to lift). But I wonder if this will even be effective, because the soil is so incredibly fine and dense.

Thanks in advance for your help.
best,
veggie


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Apr 16, 07 at 21:09

There is no difficulty building a perfectly serviceable soil that will last indefinitely in your containers. The difficulty arises when it's revealed that attention to cultural requirements may be sub-optimal.

Here is a soil that will perform well and last for at least 3 years if you add a little coarse pine or fir bark each year (you'll want to add it anyway to compensate for soil shrinkage):

by volume
3 parts partially composted pine bark
2 parts Turface
1 part sphagnum peat
1 part perlite
gypsum
Controlled Release Fertilizer
Micro-nutrient supplement

If you decide to try this soil, and you think you need more water retention, add an extra part of Turface and/or substitute rockwool for the perlite.

There will be no need to add additional peat in subsequent years.

This soil should be in the range of 6 - 6.5 pH to begin with, which is why I suggested gypsum as a Ca source rather than dolomitic lime.

Good luck.

Al


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RE: Container soils and water in containers III

Al, thank you very much for this soil recipe. I know we may have some problems with plant maintenance, but can only do our best providing appropriate plants and soil.

The only question I am left with is the Micronutrient supplement. Previously in this thread you advised that this type of mix will likely be low in MG, S, B, Zn. I looked at your link above for organic granulars, but didn't see one containing all of these. Do you have a recommendation for supplying these? I know you don't want to become a fertilizer salesman, but just a little hint in the right direction.... would be much appreciated.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Tue, Apr 17, 07 at 12:22

I use Micromax for pre-planting incorporation and STEM for maintenance after the effects of the Micromax are diminished.

Al


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RE: Container soils and water in containers III

Al, you gave a recipe for a raised bed. I realy want to do just that. It was bark, turface, crushed granite, sand. Does the sand get mixed all in everything? Or put down for a first layer? My yard is about 1ft of top soil and then all sand. I was going through the archives, and found some more info on it. But still not clear. Thanks for your help. Filix.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Tue, Apr 17, 07 at 20:29




Something close to a mix of:

5 parts pine bark
1-2 parts sphagnum peat (could use Michigan, reed or sedge peat in raised beds if you wish - prolly better)
1 part Turface (the tan stuff in the photo)
1 part sand (fine sand is as its name suggests - fine in raised beds)
dolomitic lime
CRF
should get the job done. Layer in beds & mix all well (spade fork works best).


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RE: Container soils and water in containers III

No compost? Thanks Al. My containers are doing great. Filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 18, 07 at 21:51

Sure - add mature compost to raised beds if you wish - no reason not to & it really helps in raised beds where drainage is seldom an issue. I would still use the recipe above, but include 1-2 parts compost. You could also increase the Turface & sand by a half part each.

None of this is really too critical as far as being exact in measuring out ingredients. This mix works great for me in my 5b-6a raised beds, so it should be really close to working equally well for you. You can see how rich the soil appears in the photo and you can even gauge the excellent tilth.

Al


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RE: Container soils and water in containers III

Got it! Thanks.


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RE: Container soils and water in containers III

If you didn't add compost to this raised bed mix, would you add micro-max? Filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Apr 20, 07 at 0:07

I would, yes.

Al


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RE: Container soils and water in containers III

In the world of potted citrus, there has been a movement promoting the use of well-washed coconut husk chips. This is a different product from coir - the chips are about half an inch roughly cube-shaped. The chips replace pine bark, but otherwise use a similar mix to your recommendations.
Do you have any experience of using CHC's as a growing medium?


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RE: Container soils and water in containers III

Earthbox tomatoes in Al's mix are really going well now. I thought I had mixed it wrong or my pine bark was too large, but apparently not, as the plants are really growing.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 25, 07 at 18:30

Citrange - My experience using them personally is limited, but I'm well aware of what they are & all the formulas for preparing them for use. When you sort through the websites that have information that at least looks serious & throw out the ones that have an interest in selling the product, there's not much left. Though my personal experience is limited, I have studied several texts with considerable science behind them so I'll armchair evaluate.

First, you can build a wonderful citrus soil with only two or three ingredients that will retain it's structure longer than a coir based soil (coconut products of similar size break down more quickly than conifer bark or peat), but there's no reason you couldn't include CHCs in the mix if the physical properties are suitable and there is no phytotoxicity. From what I understand, salinity can be a serious issue in some product and it should be leached thoroughly.

I have a citrus growing friend I stay in contact with, and the report I get is that CHC's can hold too much water when used as a major component of container soils. Hearsay sure, but I trust this person's judgment.

I don't spend much time on the citrus forum, but you guys should be aware of some things re coir products: They all test very high in K and very low in Ca. With a pH at generally 6+, and a serious need for supplemental Ca, there would be considerable difficulty justifying dolomitic lime as a Ca source. You should always use gypsum as a Ca source (won't raise pH and supplies S as well as Ca), which also helps overcome the low Sulfur content. Iron & copper will always be found in insufficient supply as well, so you will need to use a chelate of iron and a fertilizer or micro-nutrient (supplemental) source of copper.

Personally, I'm reluctant to try them. I know that sets poorly with someone that tries to evaluate things from a hands-on scientific perspective, but I'd be reluctant to try growing in chopped celery too, if data & reports weren't more favorable than what I'm using. ;o)

Don't view this as a slam against CHC's or a recommendation not to test or use them. It's not. Expense aside, from what I've studied and out of the anecdotes of some good growers, I think I've seen insufficient evidence to sway me from the use of conifer bark in soils for woody (plant) material.

I'll plan to try/test it this year. I'll use cuttings of three types of plant material. I'll use coleus, an impatiens, and something woody that roots easily, taking each group of cuttings from the same plant so the material is all the same genetically. I'll sub the CHC's for pine bark in half of the cuttings & do a side-by-side. Then, I'll be able to offer my actual observations.

Take care.

Al



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RE: Container Soils and Water in Containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Apr 25, 07 at 18:34

OOps - I meant to say thanks to Creister. I'm glad your maters are faring well. Don't give too much credit to the soil - you deserve the lion's share. ;o)

Al


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RE: Container soils and water in containers III

Al did you ever grow morning glorys in this mix? Justaguy brought up something I was thinking about too. Morning glorys and moon flowers are said to like poor soil. If this is true, how will they do in this mix with fertilizer and other good stuff? Just another dumb question. filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Apr 28, 07 at 8:14

As with all container soils you make yourself, you're the boss. Add/subtract ingredients as you see fit, but remember too, that all essential nutrients must be present in any soil for plants to grow properly and with good vitality. It's a given that container soils will, from the outset, be shy some nutrients; or if not from the outset, soon after planting in them they will be.

To answer the question directly: They'll do fine - I encourage you to try it and see for yourself.

Container soils are all about physical properties and structural longevity. As long as you're willing to provide the needed cultural necessities and conditions you have control over (water, nutrients, light, appropriate temperatures) and you've built sustainable aeration into your soil, almost any plant material will do splendidly in any soil that is not phytotoxic.

There - that's my entire philosophy on container soils, captured in one short paragraph.

An encouragement: Keep reading & keep asking questions, Filix. You'll soon be assembling the puzzle pieces on your own & will be able to answer most of the questions via your own reasoning! I can tell this will bring you satisfaction, so I encourage you to make it one of your goals. Your question wasn't dumb at all. In fact, it just shows that you're thinking. ;o)

Al


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RE: Container soils and water in containers III

Once again thanks Al. I feel better now. filix


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RE: Container soils and water in containers III

Al, I have been using turface and perlite, but I note that you also use crushed granite in some of your soil mixtures and seem to reference lava rock/pumice as acceptable substitutes.

Would you mind explaining what the significant differences are (as it relates to plant vitality) between turface, crushed granite, perlite and the other non organic media that you use in planting mixes.

Specifically I am wondering about things like nutrient and water holding ability compared to their value as maintainers of internal and intraparticle air spaces.

For example, why would I want to use perlite instead of turface instead of crushed granite instead of small pumice, instead of whatever?

TIA


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, May 4, 07 at 22:50

For short term plantings like veggies or flowery, pretty stuff for the display containers, I use some minor variation of the mix I listed above. For long term plantings - all my woody plant material that I have in bonsai pots, the stuff I'm growing on for bonsai or containerized maples, etc, succulents, and houseplants, I use a mix that is some variation of equal parts of Turface, crushed granite, and pine or fir bark (1:1:1).

I vary the components to fit the preferences of the plant material, E.g., for pines & junipers, I might choose a mix of granite: Turface: Pine bark at a mix of 2:1:1 or 2:2:1, depending on the container size/shape, vigor of plant material, etc. Some plants I grow in straight screened Turface - nothing else.

In general, if I need more water retention, I increase the Turface and reduce the granite. If I want less water retention, I increase the granite while reducing the amount of Turface. Personally, I never use more than 1/3 organic component in long term plantings. It guards against soil collapse & root rot issues. As I always mention though, the added vitality provided by a fast draining, highly aerated mix comes at the price of having to water frequently. BTW, Lava rock/pumice, haydite, Play Ball would all be variably suitable as substitutes for Turface rather than crushed granite.

The bark component of soils holds nutrients reasonably well, Turface has an excellent CEC and holds nutrients & water well. Granite is used to "tune" water retention, add volume, and insure aeration. Pumice is good, similar to Turface, but not as porous & doesn't have as good a CEC.

I list a variety of ingredients so others can adopt a similar soil if they choose w/o having to kill themselves looking for exactly what I use. I do appreciate the uniformity and weight provided by the screened Turface & granite over perlite (already mentioned the superior CEC). Uniformity in particle size also promotes good drainage & aeration.

Sometimes the differences are just not that significant, and can be accommodated by minor chances in the frequency of watering/fertilizing.

Summarizing: A good strategy would be to stick with the less expensive, primarily bark/peat/perlite mixes for the short term plantings, while opting to move toward the primarily inorganic mixes for the longer term.

Al


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RE: Container soils and water in containers III

If anyone wants to do their houseplants a favor they should definitely try the granite:turface:bark mix. The difference it made for my indoor plants was amazing.

I would also note that the faster draining mixes do require more frequent watering--but not as much as you might think. The superior root systems you get with increased aeration will help greatly with drought tolerance. I use coarse bark and very little peat in my outdoor mix, and never have problems with underwatered plants despite living in a hot & dry climate.

Jason


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RE: Container soils and water in containers III

Al. Once again the crushed granite is the stuff one mixes with chicken feed? You can't use crushed granite from a sand and stone company? I want to plant my trumpet vine in a long term mix. I made a large wooden container for it. Thanks. filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, May 5, 07 at 12:16

See crushed granite at lower right (Turface at lower left). Disregard the soil at top - it's a soilless mix from my raised beds & would hold too much water to be suitable in containers. It comes in two sizes at feed stores, starter grit (for chickens) and grower grit (for turkeys). It will say 100% granite on the bag. It is pre-screened and will contain no additives. The brand I use is "Grani-Grit".




Al


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RE: Container soils and water in containers III

Got it! Thankyou.


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RE: Container soils and water in containers III

What kind of top dressing could I use for my containers. I place some of my containers under the drip edge of my barn to get watered. Could I use turface or somthing to help prevent soil splashing on the plants? thanyou. filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Tue, May 8, 07 at 23:05

Use gravel, bark (not cypress mulch, please), Turface, or anything else inert you can think of. You don't need it (as a moisture conserving aid) if your containers are going 2 days or more between waterings. The need to water frequently is a plus for your plants - even if it's a negative for you.

Al


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RE: Container soils and water in containers III

Man does that soil drain fast. Even more so in the past week. We have had 80 degrees with a very dry wind. One of my containers I have had to water three times a day. This real dry weather won't last. Maybe I will add more peat to some things next time. But the plants are going gang busters! filix


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Al's mix for veggies, what about diseases?

I am currently using a promix for all my veggies in containers. I want to start mixing and using Al's mix, (at least for next year when my promix is spent and useless),but I am concerned about the blights, bacterial and fungal diseases from the pine fines. I see the bags of them stacked in the garden centers next to the plants and on the floor where they get covered with the sludge off the bags of manure and garden soil etc. and don't even get me started as to seeing the guys who load it taking a smoke break (tobacco mosaic easily survives cigarette manufacturing and can last on mulch or in the soil for years).

I always grow my own seedlings because I always introduced some new disease to my garden when I bought seedlings from anywhere, sometimes from the plants and I'll bet sometimes from the soil.

Since I've been growning only in promix, and use only hortopaper or plastic mulches, I've not had any disease problems to speak of.

What have you found to be the case as far as introducing diseases into the container veggies thru the use of the pine fines?

BTWay- I sure have found the topic of soil mix and watering both helpful and fascinating.

Thanks,
Rebecca


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, May 9, 07 at 14:59

Well - I can't say that I use them for seed starting or rooting cuttings, though I often use a handful of bonsai soil to stick unimportant cuttings in, which often contains either uncomposted pine or fir bark. I can't ever remember losing an established plant to a fungal root, stem, or vascular infection in any soils I have built, including those with a high % of pine bark fines.

Al


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RE: Container soils and water in containers III

Al- Thanks so much for such a quick response.
I think I'll mix some up next week, to try in a few big pots along with some of my seedlings when they 'ask' to be transplanted.


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RE: Container soils and water in containers III

Al I'm striking out on the grani grit. All the agway and paris framers union supplys carry oyster shells or calcite for grit. Filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, May 16, 07 at 20:16

Try coarse silica sand from a masonry supply store, or the coarsest swimming pool filter sand you can find. 1/2 BB size to BB size is what you're looking for. It will also be pre-screened.

Al


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RE: Container soils and water in containers III

Thankyou Al. I finaly got some turface. It looks alot better in the containers than perlite I think. Filix

Oh and in your raised bed mix. Do you use uncomposted bark? Thanks for your help.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, May 16, 07 at 21:13

Either in appropriate size will work, but composted or partially composted makes N immobilization easier to deal with for the first year.

Al


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RE: Container soils and water in containers III

  • Posted by donn_ 7a, GSB, LI, NY (My Page) on
    Sat, May 19, 07 at 16:36

Howdy, Al!

A quick Turface question.

My favorite nursery supply carries two types. One is called Turface MVP (Regular) and the other is Turface Soil Amendment (Quick Dry Fine). It sounds like the first (MVP) is more coarse than the second.

You've mentioned several times using 'screened' Turface. Are you using the finer byproduct of the screening, or the coarse stuff left behind?

Thanks.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, May 19, 07 at 21:27

I use Turface mainly in soils for all my woody plants, bonsai, and houseplants, but I also use it in small, singular plantings. I screen it, but it's probably not necessary for most applications you'd encounter. I only use MVP and screen through aluminum insect screening, using what's left (the coarser product). The fines, I use in raised beds and in place of sand in hypertufa troughs.

Al


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RE: Container soils and water in containers III

Al earthworms are welcome in that raised bed mix right? I made my 2x10s. Is that deep enough? I put cardboard on the ground before I added the mix. is that ok? Thanks. Filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Tue, May 22, 07 at 19:12

Sounds fine - worms & similar beneficial fauna are always welcome in raised beds - not so welcome in containers, though.

On the depth question: Yes, 9-1/4 inch depth is plenty for almost anything.

Al


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RE: Container soils and water in containers III

Thanks Al. How long will this soil hold up? You do have to add the C.R.F every year right. I think you said the second year the soil does even better. I did 4 parts composted pine bark, 1 turface 1 peat 1 sand 1 compost then some dolomite lime and I used the same C.R F. as I did in my containers. I did 4 parts pine bark because we had a week of rain and the stuff was very wet and hard to screen. I'm coming down the home stretch for all my hard work. And with your help, my plants are happy, and I have learned alot this year. Filix


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RE: Container soils and water in containers III

I have made a few mistakes whem I mixed the soil. Next year I will do things a little different. When I mixed the soil the pine bark was always damp or wet. The peat dry and hydrophobic. When I added water while mixing I noticed the peat would stay in small clumps that were dry inside. If I mixed with everthing dry as could be, then everything mixed better. But then you have to wet everything so some of the peat won't be dry half way down the pot. I'm mixing this with my hands having latex gloves on. Is there a way you can mix this dry as possible, fill your container, then water from the top and everything getting wet? I mixed in a wheelbarrow. Some of my batches were a little to wet I thing. Because when I put them in the container the soil seemed to pack rather tightly. And still is. Is there anyway to loose it up? They all have plants growing in them. Some of the soil in my containers has a crust on the top. Not sure why. Hope I'm not being too much of a pain with all my questions. filix


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RE: Container soils and water in containers III

Filix,

When I mixed mine (50% bark fines, 25% peat, 25% turface) I used 5 gallon buckets. 2 filled with bark, 1 with peat, 1 with turface.

I then flooded each and let them sit to soak up water.

Then I dumped them in a wheelbarrow.

Then I added CRT and lime and mixed. I mixed with a shovel turning everything over as I made one revolution around the wheelbarrow. That was enough.

Everything is well mixed, but I do see the small clump of peat here and there. Perhaps two revolutions around the wheelbarrow next time.

The only problem I had was the first batches were hydrophobic. To solve this I allowed the media to sit longer in the buckets and when dumping from wheelbarrow to container there was excess water left.

I am surprised that even whiskeybarrows require daily watering with this mix. I was thinking large containers wouldn't, but everything does from large to small.

So far I am not impressed with it in self watering containers. I lost 6 peppers to dessication in 24 hours and this is in an earthbox covered with plastic mulch. I think if I top water long enough for roots to reach the bottom it will be fine, but next year I will use regular bags of store bought potting mix for the self waterers.

For comparison I have a pumpkin in 2 self waters and these are doing fine, but they are planted almost to the bottom of the container and the peppers were in the top 2 inches.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, May 25, 07 at 23:34

Felix - I only added fertilizer as needed the first year. In subsequent years, I've added none, I'm in my 6th or 7th year with the soil in raised beds now. Last year I planted a stray parsley plug I had left over in a raised bed. It literally amazed me with how huge it grew. It had at least 3 times the mass of plugs planted in the garden (and my garden soil is excellent, as well).

JaG, et al - I screen my peat through 1/4 inch hardware cloth to break up all the large pieces before I mix the soil (less than 5 minutes per 5 gallons). I then wet the bark down well (not soggy) before incorporating peat & perlite. Then, I mix with a spadefork in a wheelbarrow. I never have wetting problems. I mention often that the soil will need frequent watering, but I have planted several hundreds of containers (prolly several thousand over the years) & never lost a single plant to dessication. What's even a greater contrast to what you report, is that I usually remove 50% or more of the root mass of all the greenhouse material I use in containers, which should compromise their hydraulic capabilities, but I still have no problems with roots drying out as long as I water daily. Though I don't use self watering "earthbox" type containers, I do wick water a number of small containers, and these have not been problematic either.

Al


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RE: Container soils and water in containers III

Al quick question for you. I planted my maid of orleans jasmine in that long term mix. 1 part bark 1 part turface amd 1 part sharp sand. I hope it was ok to put a handful of lime and a handful of CRF. because thats what I did. filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Jun 3, 07 at 22:25

I suppose it depends on what kind of liming material you used & to what volume of soil you added it to, eh? ;o)

The soil mix you describe should be very near or slightly below neutral pH (7.0). The addition of dolomitic lime will probably raise pH to the plants upper preferred range (7.5) or even higher. If you have water high in carbonates, you could have some pH related nutrient deficiencies show up. If you used gypsum as a liming material, you'd probably be in better shape, but I would still use an acid-forming fertilizer in either case. Good watering habits (flush soil so about 10-15% of the total volume of water applied drains from the container bottom) will help keep carbonates from building in the soil.

Good luck.

Al


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RE: Container soils and water in containers III

Thankyou Al. We got the remains of that tropical storm. Alot of rain. I looked out my window and I noticed one container was filled with water and wouldn't drain. I thought that was strange. Then I remembered that I had a bag of fafards potting soil. So I thought I would just improve it a bit by adding some pine bark and some turface to it. The four containers that I put that mix in all did the same thing. Wouldn't drain right. My containers that I have going down the driveway all have Al's mix but one. For a test I filled one with fafards. Just for yucks. That one is draining fine. Did I screw up the balance of the fafards by adding stuff? filix


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Jun 4, 07 at 22:24

I'm lost, Felix.

Al


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RE: Container soils and water in containers III

Sometimes I'm numer than a pounded thumb!:) Won't do that again. Al's mix is working just fine. I had a few pots and a few seedlings, but not enough bark fines. So I got cheap and tried to expand that bag. I can't belive I went through two truckloads of barkfines. My plants are doing great. Thanks many times! filix


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RE: Container soils and water in containers III

My experiment of putting farfeds potting soil in one pot, and Al's mix in the other is the plants in Al's mix are twice as big. Same size container, same plant, same location, watering, feeding. filix


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RE: Container soils and water in containers III

Hey, so I have a few questions which might just be common sense--but I'm pretty new to this and want to make sure I understand before I start making my own mix.

1) Is there any particular reason for incorporating peat into the mix? Could I just use regular pine bark fines? (And if I understand correctly, not using the peat would mean I should use gypsum, not domolitic lime for adding Ca so that I don't inadvertantly cause the soil to become too alkaline?)

2) Assuming that I want a standard mix for long-term container indoor and outdoor plants, as well as some veggies, this is the sort of mix I am imagining--could you critique it? :-) where exactly would the addition of worm castings to the intitial mix fit in? As a micronutrient supplier/time-release fertilizer? How much of my plant's required nutrient needs could be filled by the worm poo, since its rated 1-0-0 (even though I've heard that the rating is innacurate, and it is instead balanced)?

3 parts pine bark fines
1 part worm poo
2 parts turface/granite <--how do I choose the correct proportions, can I just go straight with turface OR granite, and what does that mean for my plants? and should I consider perlite? Although from what I've read, it might just be better to go with turface and granite--although perlite is cheaper...
CRF
gypsum

would 4:2 organic:nonorganic be too dense for the mixture? And so should I reduce the wormpoo or the pine bark?

Thanks so much!

Amanda


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Jun 29, 07 at 18:25

1) Peat is kind of optional, but I like how it tends to help keep pH on the south side of neutral. Whether or not I would use it also depends in part on the particulate size of the other ingredients. E.g., if the bark size is larger, like mini-nuggets instead of fines that are partially composted, I'd use peat mainly for the added water retention.

If you don't use peat & are using a soil that is low in organic material, I would suggest gypsum as a Ca source unless you are growing plants that like a higher pH, so you are correct.

2) Truthfully, I would skip the worm castings in container soils. They do add a little in the way of micronutrients, but nothing you couldn't easily accomplish chemically or organically with the addition of any one of a number of fertilizers or supplements that include the minors.

I would usually not use Turface in soils that are intended for short term plantings like annual veggie crops or "pretty flowers". ;o) I Use Turface in soils for plantings I intend to be in the same soil for more than a growing season or for bonsai or plants in very shallow containers where drainage is critical. For long term plantings, I use a base soil of equal parts of uncomposted pine or fir bark, Turface, and crushed granite. I vary the amount of Turface/granite as needed to optimize the amount of water the soil holds. You may very well be able to eliminate the granite if you are in a hot or windy area. The equal parts mix is excellent for cacti, succulents, and houseplants in general. With only a couple of other amendments added, you can usually fine tune this mix to suit anything you'd like to grow. The mix you suggested is quite close to something I might use, except for the castings.

Good luck, Amanda.

Al


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RE: Container soils and water in containers III

I don't see granite in the same class as perlite or that the use of perlite as an issue of economy. Commercial growers and professional and home gardeners use perlite for functionality: moisture retention, soil aeration, commercially used and well studied for its multi-functionality, easily accessible, consistency and durability, pH neutral, and light wt for storage, carrying, use, and transportation where unique individual benefits as well as insurance for solid building structural support for intense cultivation in small spaces may be of primary concerns.

A soilless medium for containers serves only to provide efficient root uptake of air/water/nutrients and some structural support and anchor needed by a plant. The amount of root support is minimal, for an outdoor banana tree can be grown successfully with a light-weight potting mix consist mostly of perlite and some coir). The specific ingredients are not as important as a final mix that would allow the roots to function optimally in a range of these native preferences with a given light exposure and climate, because plants, like all living things, are adoptable to a range of seasonal and environmental changes.

Mixing the right potting mix is simple and should be open to fine adjustments suitable for a micro-climate. If things don't work out, a good gardener can always amend and repot base on observable symptoms exhibited by a plant.

There are many published successful soilless recipes in use commercially and privately. There simply is not one ideal soilless mix. There may be a basic mix with which to build upon to be successful but bear in mind that one-size-fits-all potting mix does not exist. Three major reasons are that horticulture requirements amongst plants, local growing conditions and climates (and growing method/planters used), and natural regional resources vary widely. Even within similar regions but different growing conditions, for example, turface and granite amendments may serve little horticultural or operational benefits than a simple higher percentage use of perlite for shady, greenhouse, and balcony gardens or nursery growers and female, young, and senior gardeners with large collection of planters where lifting Truface and granite and planters can be major gardening and maintenance obstacles, while these ingredients may serve ground level containers or raised beds in dry and windy climates and open growing conditions better. It's important to consider what is preferred or considered ideal by one gardener or in one growing condition may not be ideal or preferred for the next.

The basic reason behind making one's own mix is the flexibility and hopefully the ultimate success such flexibility would enable a gardener in meeting first the horticultural needs of a plant with respect to a given local climate and any unique micro-climate and growing conditions and limitations along with personal economics and accessibility of an ingredient and any secondary personal preferences. Before one can identify the necessary ingredients of a good mix, one needs to know and MUST ASK what preferred air to moisture retention ratio, suitable pH range, and drainage preferences are needed and required by my plant to grow optimally, what unique limitations in my current growing conditions (light/wind/rain/cumulative wt. of planters and materials) are in meeting these native requiremnts, and then what specific functions does each amendment serves to provide for the needed conditions along with a gardener's personal preferences and objectives.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Jul 1, 07 at 12:09

Interesting - thanks for the thoughts. You'll find everything you just said, above, and/or in a previous thread on the same topic, if you sift through the thread. ... nothing to disagree with.

Al


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RE: Container soils and water in containers III

So supposing that one is using a mix in which water retention is not an issue, instead of using peat as what seems to be a soil ammendment to create a mildly acidic soil pH, could one theoretically use spent coffee grounds to the same effect (with its availability being greater, and its acidic properties)? Does anyone know exactly/generally how much coffee grounds change soil acidity per unit measure?


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RE: Container soils and water in containers III

They really don't. Brewed coffee grounds aren't strongly acidic, but near neutral in pH. The acidity is in the coffee itself.

The water and fertilizer you use will have a stronger affect on pH than the potting mix.


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  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Jul 2, 07 at 6:40

In addition, coffee grounds break down quickly, making them generally unsuitable for use in containers. They are also extremely hydrophobic (water repellent) when they dry down to below 30-35% moisture content.

Al


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RE: Container soils and water in containers III

It has been written that brewed coffee grounds is pH neutral as well as mildly acidic. I have not tested the actual pH myself or researched into it. I know for sure recycled coffee grounds can provide quick but safe usable nitrogen supply to containerized acid-loving gardenia with the pH controversy aside.

A year or so ago when I was drinking coffee (just started recently again - might as well for my gardenias), I piled on (top dress) used coffee grounds DAILY on my container gardenias that also didn't get get acid-loving fertilizer. I did it for the pH reason initially to keep the potting mix acidic, and the spent coffee grounds turned any early yellowing foliage green virtually overnight. The acid-loving container gardenias seem to respond and thrive to the added coffee grounds noticeably either from the pH (whatever it is) or the nitrogen, including its quick-draining and texture which I know gardnias prefer. Any possible water-repelling texture or property of the coffee grounds seemed to be perfect for container gardenias and have made an ideal organic mulch for humidity-loving gardenias as well and without destroying the total porosity and making the potting mix sticky. These observations are not based on one acid-loving gardenia but three containers of the same variety - Veitchii.

I recall I read somewhere a few days ago that gardenias are of the coffee family (interesting), but I didn't verify this fact or look into it. I wonder if we could grow gardenias successfully or easily in high percentage recycled coffee grounds?


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RE: Container soils and water in containers III

With some precaution and maintenance, a gardener can also substitute peat for proven certified coir for higher water retention, better rewetability, and durability and stability (2-4x) with a pH of 5.5 to 6.8.


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RE: Container soils and water in containers III

  • Posted by ecosse 8a Southern Nevada (My Page) on
    Sun, Jul 22, 07 at 15:22

Repot (its 110), wick it for now, or?

Hi- Found this thread a week ago and its been bedtime reading since-all 400+ posts. Bless you, Al, you have the patience of a saint with us!

Wish Id found it earlier- At the end of May, I lost a number of plants in my balcony container garden due to soil/ drainage issues. Especially painful was losing some mini roses. The leaves started browning from the outer edge, mummifying. A nurseryman told me then there was not enough water uptake available for any number of reasons (all in this thread!) and the heat exacerbates the issue.

I bought a Peach Brandy Mini from him (well, hed given a free diagnosis ;-). Besides, it was sitting there in a one gallon growers container on a bed of gravel in full sun at 100 degrees and looked happy. (and was clearance priced). Was potted in what appeared to be about 70% coarse sand and 30% mulched wood products. Very fast draining.

Tried to replicate the soil, (this before reading Als -taplas- article) ended up a mixture of a sand based succulent/palm mix, potting soil, pumice, and perlite, and repotted in a 12 inch pot, cached inside a 14 in pot lined with old newsprint (for insulation)

2 weeks after, temps here were 118, on my (south facing) balcony about 120, and on this new one, about 50% of the leaves were doing the browning thing. Checked, and although the pot drained quickly, it was also holding a lot of moisture. Now, at 6 weeks, the browning has stabilized -tho still there-and there is a touch of new growth. If we can just make it through the summer

So

Should I repot (temps will be over 100 here til Sept, overnights in the 80s) using a modified (add pine bark -well, sifted orchid bark-and more pumice) version of Als recipe? Modification due to financial and availability constraints. (Pine bark here is available in sizes you could use in a fireplace, no wood chipper available, dont think my old food processor would survive ;))

Wait for cooler weather, poke a wick up inside for now?

In either case, fertilize? I have Osmocote and some liquid emulsion charmingly named "Fish and Poop". Seriously. Do NOT open indoors =0

I noted in an earlier post, Al suggested using pumice as a cache-pot insulator. Can do. Hmm. Maybe vermiculite? Breathes, holds moisture- for evap. effect?

Thanks! Special one to jdwhitaker for keeping thread alive-and hot/dry advice!


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Clarifying my previous

  • Posted by ecosse 8a Southern Nevada (My Page) on
    Sun, Jul 22, 07 at 18:32

Sorry-missed in the edit

"using ***my soil in*** a modified (add pine bark -well, sifted orchid bark-and more pumice) version of Als recipe?"


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  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Jul 22, 07 at 21:13

I'm pretty confused, but you should add a wick if the soil isn't drying down after a day or two and you should NOT repot out of season, especially in that heat. Potting up would be ok, but there is a difference between repotting & potting up that you may not yet discern. Repotting entails root-work - potting up does not.

Use anything in the cache pot that is not phytotoxic and that will breathe while holding good amounts of moisture. Cooler (than your ambient) root temperatures are required to insure good plant vitality.

Try not wetting foliage when you water to help stop burned leaf margins and fertilize as required when the plant is actively growing. Most plants take a little siesta when temperatures get to the extremes you described & fertilizer is largely unnecessary during the quiescent period.

Al


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RE: Container soils and water in containers III

Hey Al, excellent reading. Thanks for sharing all that you've learned through your years of personal research and experimentation. I've learned a lot reading through this whole thread (took a long time!).

Do you ever lend your expertise to the folks in the cacti/succulent forum? I've been there everyday for the past month as I'm getting very interested in succulents, especially mesembs. I've been using Steven Hammer's suggested "mabel mix": two parts loam, one part coarse sand, one part pumice. I think most of the folks over there use this as well.

Have you ever experimented with any cacti/succulent (especially the smaller mesembs) soil mixtures? If so, your experience would be most welcome.

Thanks again for all the great info!


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Jul 23, 07 at 10:14

I'm no cacti/succulent expert, but I have quite a few - mainly succulents. I've settled on a mix of:

6 parts screened Turface
3 parts starter grit (crushed granite)
1-2 parts uncomposted pine or fir bark (1/8-1/4" chunks)
1 part coarse silica sand
1 part vermiculite
Micromax (micronutrient source)
gypsum or egg shells

This is an easy mix for me as I usually have several cu ft of bonsai soil mixed up/on hand & I just amend it with additional Turface and granite, then add in the silica, vermiculite, and a Ca source.

Contact me off forum & I'll send you a small bag for your "evaluation". ;o) I'm pretty sure you'll really like it.

Al


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RE: Container soils and water in containers III

Let me offer a testimonial on how good the soil mixture listed on the top of this post has worked for me this summer. Previously I only used soil mixtures I bought at stores. This year I used Als soil mixture for about 30 containers all containing either geraniums or lobelia and hooked up to an automated drip watering system. My flowers are the fullest, nicest looking, biggest growing that I have ever grown. I cannot believe how large the plants are in such small containers that I have provided. I have several other plants that were kept in their original containers and also watered with the drip watering system. They not doing nearly as well. I cannot seem meet their watering demand (either they are too wet or too dry) because of the soil - it retains too much water.

With Als soil mixture, the water drains immediately after watering but retains enough water to keep the roots moist until the next watering. If I had to recommend anything, it would be to use an automated water system with this soil mixture. In hot weather with small containers, it will dry fairly quickly.


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RE: Container soils and water in containers III

  • Posted by ecosse 8a Southern Nevada (My Page) on
    Mon, Jul 23, 07 at 13:36

Al-

Thanks for giving me the answers to my concerns! (Sorry I gave too much info)

Much appreciated!


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RE: Container soils and water in containers III

Hi again, how is everyone?

Having carried all of the pine bark, 50lb. bags of turface, etc. up to our 3rd fl. roof and mixing it myself due to my younger, stronger, more athletic husband's hernia history, I am wondering what "legacy" means by "female".

I would also like to say that my plants are doing swimmingly, without drowning of course, thanks to Al's mix, and Al and Dorie's wonderful advice.

Thanks again and agian, Amy


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Mon, Jul 23, 07 at 18:57

Such kind words from (almost) everyone lately. Thanks to all for taking the time to tell of your findings and results. Thanks too, for the questions that keep the thread interesting & active. I've had lots o' fun & have made plenty of pals over the last few years at GW & particularly here on the Container Forum. You guys ROCK! ;o)

Al


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RE: Container soils and water in containers III

I tried brown dress shoe thin nylon laces cut in half the taped or glued end is pushed into the soil than I use something thin to push it in further - I find this only works for really waterlogged soils - If the soil is moist but not soaked it will not work - One pot I have that I just flushed yesterday has filled up half of a tupperware container and is still dripping - maybe there are more materials that wick better but the one pot started wicking right away as soon as I pushed it into the soil - I tried running shoe laces didn't work at all. I think this may have something to do with an already mature root mass at the bottom of the pot - if there is a substantial mass it doesn't seem to work for me.

cheers

Jeff


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RE: Container soils and water in containers III

Ran by my local nursery today to pick up some perlite and they actually had a new pallet of pine bark fines! Shocked the heck out of me since I had been calling them almost daily for the past week. On the phone they claimed to never stock the stuff and said they don't sell the stuff they use for their containers. But low and behold they got a fresh pallet in just today! Picked up 3 bags.

Al, contacted you regarding evaluation bag. Thanks again for all the great info!


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RE: Container soils and water in containers III

Well I want to add my thanks to Al as my 100 pots are all doing wonderfully. I have never had this much success and have gardened for 30+ years. I do have drip irrigation but I dont think it is responsible for the success. The mix gets wet easily but dries out and doesnt seem to be waterlogged.

I do have one question. I used part soil conditioner and part small bark chips for most things. Some bark chips are 1/2 to 3/4 in. I used more of the bigger ones in the long term planting. I have since read everything should be the same size?? Also I have only used bags of bark chips. Probably fir as I am in the PNW.

None of it was composted.
When do you need composted and how do you compost it?


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Jul 25, 07 at 9:07

;o) Thank YOU too, for the kind words, E. I'm soo happy for you! From our conversations, you know I use some soils with a very high (often 100% or near that) % of inorganic ingredients. I usually ALWAYS use an uncomposted bark in these soils (fir or pine, depending on a couple of factors) because the intent of using such a high % of inorganic materials is soil longevity and resistance to collapse over a longer expected life. The key consideration is that there is such a small % of bark in the soil that N immobilization is generally never an issue.

I prefer a composted bark product for all my short term plantings ("pretty flowers" and veggies, or stuff I'm just playing around with). The two reasons for that choice are economics and N immobilization. Less N is tied up in partially composted bark than in uncomposted, and in a soil where 3/4 or more is bark, that effect can be significant if not addressed. It's not a huge problem though (if you use an uncomposted conifer bark), as long as you're cognizant of the fact that you will be required to furnish the plant a diet higher in N to maintain best vitality.

Take care - good to hear from you.

Al


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RE: Container soils and water in containers III

Well i am glad I am on the right page. I thought I was then I read a little more and get confused.
If one was to judge by the look of the plants in my containers i dont think I need to add or do anything else.

I do wonder about my house plants. I use weak S.T.E.M. every time I water. Do I need to feed them with a NPP fertilizer once in a while?
Thanks again for all your help.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Jul 25, 07 at 21:12

Oh yes. STEM supplies primarily the minor elements in soluble form. You'll still need to supplement the macro-nutrients, (N)-Nitrogen, (P)-Phosphorous, (K)-Potassium, Magnesium, and Calcium. W/o looking, I think STEM contains adequate Sulfur. In general and for a high % of plant material, I would suggest MG 24-8-16 in a soil with a high organic content and something like a balanced fertilizer (20-20-20 eg) in a soil with a high mineral content (Turface, granite, pumice, etc).

Al


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RE: Container soils and water in containers III

CONFUSED !

It appears that Al's recipes below are not the same for both batch sizes. The generic recipe is 3:1:1. The big batch seems to come out to about 4:1:1. The small batch looks like about 6:1:1. Which is it? or doesn't it really matter? or am I totally in error?

Thanks to all,

Bob Nlight


PREVIOUS POST WITH AL'S RECIPE

My Soil

I'll give two recipes. I usually make big batches.

3 parts pine bark fines
1 part sphagnum peat (not reed or sedge peat)
1-2 parts perlite
garden lime
controlled release fertilizer
micro-nutrient powder (substitute: small amount of good, composted manure

Big batch:

3 cu ft pine bark fines (1 big bag)
5 gallons peat
5 gallons perlite
1 cup lime (you can add more to small portion if needed)
2 cups CRF
1/2 cup micro-nutrient powder or 1 gal composted manure

Small batch:

3 gallons pine bark
1/2 gallon peat
1/2 gallon perlite
handful lime (careful)
1/4 cup CRF
1 tsp micro-nutrient powder or a dash of manure ;o)


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RE: Container soils and water in containers III

Technically bob you're right b/c a cubic foot is about 7.5 gallons (according to google calculator). So yeah, the ratios are a little off.

However, I'm assuming that when you're dealing with a large volume such as is listed above it would be a little tedious, time consuming, and difficult to get things precise. Al probably mixes up several of his large batches each year. I just spent 2 hours screening my latest pine bark earlier this morning. TEDIOUS! Let me tell ya, it was fun when I did it for the first time last week. Today it was a major drag.

Dealing with huge quantities can only be fun for so long! :)


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Aug 9, 07 at 22:30

You're right, Bob. I've addressed this a few times upstream. I usually use somewhere around 5 pine bark fines, 1 peat, 1-2 perlite, plus the other ingredients, but it really wouldn't matter too much if you used the 3:1:1 ratio. It would still drain immensely better & hold much more air for longer than primarily peat soils.


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RE: Container soils and water in containers III

Thanks for clearing that up for me. I thought I had read something about a correction to 5:1:1 but couldn't locate the post to clarify and I've got a batch waiting for me to finish.

Is my estimating correct that with this recipe you would use about 1/2 cup CRF per cu. ft of mix and about 1/4 cup lime per cu. ft. of mix?

Also wondering about the screening aspect. I've screened my peat at 3/16" but my bark fines (Greensmix - so glad to have them) looked pretty good right out of the bag. Do you screen the peat AND the bark fines? What size screens do you recommend.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Aug 10, 07 at 0:52

Yes - the lime & CRF are about right. You only need to be close on your ingredient volumes. It's not too critical.

I don't really screen peat for size. Rather, I push it through a 1/4" or 3/8" hardware cloth soil sieve to break up or "strain" the large chunks and sticks from the rest of the peat.

I have 2 sets of 5 screens that I built & use regularly. 1 set is about 24" square and 3-1/2" deep - the other is about 15" or 16" square and about 2-1/2" deep. They are hardware cloth in 1/2, 3/8, 1/4, 1/8, and insect screening. When I'm using pine bark, I only screen the bark for my soils that I use on woody plant material and that will need to last more than a single grow season. I use screened, uncomposted bark in these long term soils. I discard (in the gardens or beds) all that passes through an 1/8" screen and all that remains above a 1/2 or 3/8 screen, depending on what size plant/pot combination I'm using the soil for. I use unscreened, partially composted pine bark in all my veggie & "pretty flower" plantings or any other short term plantings.

Lately, I've been fortunate enough to be able to find 1/8 to 1/4 prescreened fir bark at $15/4 cu ft. I've been using this pretty exclusively in my long term soils with very good success and minimal effort (prescreened).

Al


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RE: Container soils and water in containers III

That clears it all up for me.

Thanks to Al and zeckron for the help and advice!

: )

Bob
WI-Nlight


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RE: Container soils and water in containers III

  • Posted by amyben 7Bklyn., N.Y. (My Page) on
    Mon, Aug 27, 07 at 10:48

Shouldn't this paper be required reading for container gardeners? Let's send it to the first page, at least, for fall and winter preparation for spring.


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RE: Container soils and water in containers III

I used Al's formula for my containers! Wonderful results -even in the drought in the NE. I also amended a spot in my yard where grass would never grow & it was matted w/ thin roots and very, very poor drainage. I didn't have the correct amts of all the products for the 3:1:1 ratio - just sorta eyeballed it using up the leftover pine bark - sorta made a raised bed - and for the 1st time in 7 years that area is growing. Planted a rose bush, 2 elephant ears, moved plants from other areas and it all looks great - considering the heat, drought & I did this in July!
Al, I love this soiless mix! I gave a copy of it to the guy at the farm supply where I readily found the ingredients - hope you don't mind - I gave credit to you and this site - I kept going back for more pine bark & he was curious - he gave me an uprooted Rosemary plant - it did great in the mix. We live in the "suburbs" but have a great family owned Farm equip & supply feed store - lucky me! I am horrible at fertilizing - so nothing got anything extra - except alot of water. Just wanted to tell you Thank you!!!!


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  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Sep 5, 07 at 16:59

Oohhh! Thank you for sharing your success with us, M! Everyone loves kind words, and I'm no exception. I'm glad you're gaining a feel for soils, & I'll hope now that you expand your base to include some knowledge of plant fertilizers and nutritional requirements so you are even more successful. Combine the above with a good watering technique & you'll be unstoppable! ;o)

Take care.

Al


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RE: Container soils and water in containers III

Al, I 'm glad you got my little Thank you note - I do have a question, if you don't mind. Because my containers freeze & break, I try to empty them before winter for storage. I think you said we can get a 3 yr cycle out of this mix. Do you recommend just dumping all the good mix -minus the plants (and any that had bugs or problems) together in a big trashcan and store til spring? Then I was thinking of giving it a boost of some of the nutrients and slow release fert. before the next plantings. What do you recommend?

I did get some mildew on some of my annuals - it was from the very humid nites & high nite temps - so I wasn't going to combine that mix - but I am going to reuse it.
Also for the wick, I used a blue micro fiber cloth that I cut into stripes- I have alot of hanging containers - so they were good for conversation - until the theory went way over most peoples heads. Not that I am that smart -I had to read your info about 10 times until I got it. I will never go back to store bought soil. I love it!
Thanks again for sharing your wonderful recipe and all your time spent answering these questions.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Sep 6, 07 at 20:55

You're welcome. Thanks again, for being so kind.

Some thoughts I offered in another, older threads on this forum. They should pretty much answer your question, and may even be quoted in the text somewhere up this thread (if so, I apologize for the redundancy):

In my estimation, the only case to be made for reusing container soils is one of economics, and you'll never find me argue against making that decision. If you can't afford, you can't afford it. That said and setting economics aside, you might decide to reuse soil for reasons other than economical. Perhaps the effort involved with acquiring (or making your own) soil is something you might not wish to go through or be bothered with.
In any case, it would be difficult to show that soils in a more advanced state of structural collapse can somehow be preferred to a soil that can be counted on to maintain its structure for the entire growth cycle. So, if the economic aspect is set aside, at some point you must decide that "my used soil is good enough" and that you're willing to accept whatever the results of that decision are.

All soils are not created equal. The soils I grow in are usually pine bark based & collapse structurally at a much slower rate that peat based soils, yet I usually choose to turn them into the garden or give them over to a compost pile where they serve a better purpose than as a container soil after a year of service. Some plantings (like woody materials and some perennials) do pretty well the second year in the same bark-based soil, and with careful watering, I'm usually able to get them through a third year w/o root issues.

Watering habits are an extremely important part of container gardening. Well structured soils that drain well are much more forgiving and certainly favor success on the part of the more inexperienced gardeners. As soils age, water retention increases and growing becomes increasingly difficult. If your (anyone's) excellence in watering skills allows you to grow in an aging medium, or if your decision that "good enough" is good enough for you, then it's (your decision) is good enough for me, too.

The phrases "it works for me" or "I've done it this way for years w/o problems" is often offered up as good reason to continue the status quo, but there's not much substance there.

I'm being called away now, but I'll leave with something I offered in reply on a recent thread:
"... First, plants really aren't particular about what soil is made of. As long as you're willing to stand over your plant & water every 10 minutes, you can grow most plants perfectly well in a bucket of marbles. Mix a little of the proper fertilizers in the water & you're good to go. The plant has all it needs - water, nutrients, air in the root zone, and something to hold it in place. So, if we can grow in marbles, how can a soil fail?

Our growing skills fail us more often than our soils fail. We often lack the experience or knowledge to recognize the shortcomings of our soils and to adjust for them. The lower our experience/knowledge levels are, the more nearly perfect should be the soils we grow in, but this is a catch 22 situation because hidden in the inexperience is the inability to even recognize differences between good and bad soil(s).

Container soils fail when their structure fails. When we select soils with components that break down quickly or that are so small they find their way into and clog macro-pores, we begin our growing attempts under a handicap. I see anecdotes about reusing soils, even recommendations to do it all over these forums. I don't argue with the practice, but I (very) rarely do it, even when growing flowery annuals, meant only for a single season.

Soils don't break down at an even rate. If you assign a soil a life of two years and imagine that the soil goes from perfect to unusable in that time, it's likely it would be fine for the first year, lose about 25% of its suitability in the first half of the second year, and lose the other 75% in the last half of the second year. This is an approximation & is only meant to illustrate the exponential rate at which soils collapse. Soils that are suitable for only a growing season show a similar rate of decline, but at an accelerated rate. When a used soil is mixed with fresh soil after a growing season, the old soil particles are in or about to begin a period of accelerated decay. I choose to turn them into the garden or they find their way to a compost pile.

Unless the reasons are economical, I find it difficult to imagine why anyone would add garden soils to container soils. It destroys aeration and usually causes soils to retain too much water for too long. Sand (unless approaching the size of BB's), has the same effect. I don't use compost in soils because of the negative effect on aeration/drainage. The small amount of micro-nutrients provided by compost can be more efficiently added, organically or inorganically, via other vehicles.

To boil this all down, a container soil fails when the inverse relationship between aeration/drainage goes awry. When aeration is reduced, soggy soil is the result, and trouble is in the making.

I've mentioned before that I don't post here to get people to convert to a particular mix or blend of soil. I post what I know will work very well for anyone who can get appropriate ingredients & modify the mix to suit their climate & other cultural conditions. If you use a mix that guarantees good aeration for the expected life of the planting - you're in good shape. Most peat based mixes will not work well in extended life plantings. Conifer bark based mixes, on the other hand, retain structure for much longer periods.

If you still have questions, please don't hesitate ....

Al


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RE: Container soils and water in containers III

I was so happy to find this article when I was a newcomer, that I must send it to the first page. I guess soon it will max out and someone will re-post. Until then, let's keep it handy.


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RE: Container soils and water in containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Sep 23, 07 at 18:38

Thanks, Amy!

This thread is ready to be terminated, so I will provide a link to a new thread for any interested. Scroll down to the next posting for the new link.

Al


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RE: Container Soils and Water in Containers III

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Sep 23, 07 at 18:44

Click on the link below to view a continuation of this thread in part IV.

Al

Here is a link that might be useful: Container Soils - Water Movement & Retention IV


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