I don't think you have to worry. For what it's worth, here is what the University of Idaho says:
"To avoid nitrogen depletion when incorporating uncomposted hardwood products into the soil, add 25 pounds of actual nitrogen with each ton of sawdust or bark. Incorporate about 12 pounds the following year. For uncomposted softwood materials, incorporate about 12 to 13 pounds of nitrogen with each ton of sawdust or bark and incorporate 6 to 7 pounds of nitrogen the following year. Any kind of nitrogen fertilizer can be used."

Now, we could run the math, but I think that down at 5% you have no worries. Especially if you plan on any kind of liquid feeding for your pots. Probably standard rates, or even 1/2 or 1/3 standard rates, are enough.

Maybe edge up your fertilizer schedule for nitrogen slightly, but no more.

Here is a link that might be useful: Reference PDF

This post was edited by johns.coastal.patio on Sun, May 18, 14 at 11:21

It is rare to find pine bark fines by whatever name that don't include some sapwood. In past discussions on this forum, people who use versions of Al's recipes generally agree that you don't need to worry about it unless it makes up more than 10-15 percent of your bark. Just pick out the larger sapwood pieces as you combine your ingredients. There is no need to go back and remove the mix from your pots that have already been filled.

Since the 5-1-1 and gritty don't contain any nutrients on their own unless you add the lime and controlled release fertilizer when you make them, you are advised to fertilize regularly during the season. This is a good idea with almost any container mix, including the store-bought ones that promise to feed your plants for months, because nutrients, in particular nitrogen, are leached out a bit every time you water.

There is a "sister" thread to the Container Soils thread that talks about fertilizing container plants. Al recommends using a fertilizer with a 3:1:2 ratio of nitrogen, phosphorous and potassium as well as trace minerals. You can use a soluble fertilizer like MiracleGro all purpose 24-8-16, which is easy to find, or you can spend a little more and use DynaGro FoliagePro, which is available online. There is no need to become a plant scientist who devises his own mix, unless of course you want to. If you are interested in learning why the 3:1:2 ratio is recommended, follow the link below. But these recommendations are intended to help beginners who don't care about the details as well as those of us who are fascinated by the science and want to fine tune their growing experience.

Here is a link that might be useful: Fertilizing Containerized Plants

NewContainerGrower,

I agree with the other posters here, that the amount of sapwood in your soil mix is probably not an issue. As Ohiofem said, I don't think I've ever seen pine bark without any sapwood at all. Nearly every bag of bark will have some sapwood, that's just natural. If you have a high percentage of sapwood then you can pick through the bark and remove what you can. That's what I do.

The lime you add when you create your mix, plus the regular applications of fertilizer, should negate any problems with your sapwood.

I don't think you have anything to worry about here.

Hope that helps.

TYG

It is kind of interesting to note that MiracleGro made their name as a 15-30-15 fertilizer, and after a series of changes, ended up at 24-8-16.

I'm sure it works, but I think the earlier ratio (still found on some "clones") works as well.

The old formula is wasteful. Plants simply don't use that much Phosphorous (in relation to the other nutrients).

Josh

That's probably true, Josh. And now we know that phosphorous runoff is a problem in many areas (though containers contribute much less than lawns!).

MG "Flower Food" is still 15-30-15, and their "Tomato Food" is 18-18-21, for two more data points.

I do slightly mistrust the "tissue analysis" logic. It's the Gatorade problem. Sure, Gatorade matched the chemical analysis of sweat (yuk!).. but that didn't actually mean you should drink it ;-)

Thanks a ton everyone! Ok, huge relief. I am really looking forward to plant out now, hopefully June 1 will hurry up and get here.

Oh and I have a 312 fert ready to go. I guess I just missed some of the sapwood details in my readings. Truly appreciate the advice.

So, do tomatos use nutrients differently than most plants? Do they need 18-18-21 as oppose to the 3-1-2 ratio?

"So, do tomatos use nutrients differently than most plants? Do they need 18-18-21 as oppose to the 3-1-2 ratio?"

Every single type plant the ratio would be different. The 3-1-2 is a general guess as to what works most of the time. Every species is different. Some cannot even uptake many nitrates, and need nitrogen in other forms, such as blueberries. Some fix nitrogen and don't need any.
With tomaotes yes the MG ratio is better. Although I myself like to give them higher nitrogen the first couple of months, then decrease the amount. Peppers too. Most fruiting plants are like this, but exceptions exist. Raspberries don't mind a steady amount, fruiting or not. Even within a species different cultivars have different needs. A lot depends on where they originated.
Al's suggestions about potting mixes and fertilizers is like horticulture for dummies, it works in a general sense, but for a more serious gardener, the info is rather general. A good starting point. I like the info as it points to what is important and as you learn more, you can adjust to fit your specific needs. People often try to say potting culture is the same everywhere, but it is not. Enviromental factors matter.
Plant species matter too. You would not treat a lima bean, a blueberry, a tomato or a spider plant the same, that would be a huge mistake.

I agree with that Drew, but I suspect that even when we do the common "application at half-strength" we are giving the plants plenty. For container plants, liquid application is a passing thing. Plants will grab what they like, and the rest will drain away.

Certainly at high rates of application, "excess nitrogen" and etc. are possible ... but I don't think at half-strength, every two weeks.

I transplanted my tomatoes in my 5-1-1 containers on May 10th and they're growing fantastically so far. I also am new to 5-1-1 and did not pay much attention to sapwood that made it through my 1/2" hardware cloth. We'll compare notes as the growing season moves on.

Hey njitgrad,

Good to hear! I ended up only removing the larger pieces as well and tried to mitigate the sapwood left in them with a time-release fert. See how things start and then I'll get into the weak liquid ferts as well.

I planted out into my 60 3gallon pots yesterday so fingers are crossed. Since this is my first attempt at this mix I did a backup of a few of my more important cultivars in a peat/compost/perlite mix. At the very least it will be an eye-opening comparison.

Have to admit it felt good to give'em a good drenching without the worry of over-watering!

Regarding the sapwood issue, as long as your final bark mix does not contain a large amount of sapwood you should be OK. Each bag of pine bark, except perhaps the high-end orchid mixes or the ReptiBark, will have SOME sapwood. that's pretty much unavoidable. Just screen out,or remove by hand, as much of the sapwood as possible. Usually not a big issue unless your bark source contains a lot of sapwood.

TYG

Like Ohiofem said, it is almost impossible to find bark product without sapwood. When they shave the bark off the logs, naturally some sapwood is shaved too. And we now that bark products are marketed in landscaping business as mulch. So they are not going to be too picky about sapwood.

If you are concerned, you can screen them. Most sapwood pieces are bigger then bark pieces. OR just manually pick them if there is to much of it

Here is what I use :

(1) small pine bark nuggets (on the right) and pine bark mulch (left). The nuggets have no fines but the size is mostly 1/2" and smaller. The crushed mulch is mostly smaller than 1/4". So mixing those two (50/50) I get a goo structure.

Ah, the search continues to find the elusive Pine bark fines!
I am in awe of Al's vast knowledge and in fact, became a Member of the Garden Web after reading the "Al Chronicles" in seven (or is it 8 now?) Volumes.
Al, you are the Zen Master of wicks, water plateaus, and medium mixology!
.....but I digress.
I wanted to mention one source of nitrogen that will slow release and is more to my liking as it doesn't come out of a bottle (though it does come in pelleted form), which is Alfalfa Pellets. (the horse kind, not the rabbit).
The pellets will swell and fall apart as soon as water is applied and offer a quick fix of readily available nitrogen to offset those pesky sap woods in your pine bark nuggets.
For my OCD tenancies, I don't care for any of the bagged bark products available from your local Home Improvement Palaces, because in my estimation, none qualify as true Pine Bark Fines.
What I consider pine bark fines is always PARTIALLY COMPOSTED PINE BARK, which by it's very nature, you can crumble into bits through a diamond mesh screen.
Almost without exception today's "Forest Products" are the byproduct of lumber harvesting, which is ground up and dispensed into bags. Nothing even approaching composting of pine bark is occurring with these products because it takes too long.
I haven't found a reliable source of "fines" other than harvesting my own from around the bases of harvested Ponerosa pines cut over a decade ago.Old timber operations often left the bark and branches piled at the harvesting site, which is another good source, as are old dead snags, which will have the bark slip from them and land about their bases.
All of this requires a bit of labor on your part, but then again, it's a lovely way to spend the weekend, right?
National Forests in California are quite accommodating and will issue a permit if required, or happily point you in the direction of a likely spot to forage. I can usually fill my pickup truck bed in about 4 hours and all it costs me is my time and gas for the truck.
I attribute my OCD behavior on the subject to an ancient Bonsai Master I had the privilege to study under back in the late '60's, who was very exacting in his tutelage.
"Fines" were exclusively "Partially Composted Pine Bark", period.

@ Sierra ...Welcome !

Without going into details of your post , I have difficulty with the phrase " COMPOSTED BARK FINE"

I said I have difficulty with understanding it, b'cause, if anything is composted then it is not what it previously was. That means if pine bark fine is composted then it is not going to be pine bark fine anymore. It will be just composted organic matter.
Lets say that you mean halfway composted. Then it should continue composting in the pot /container ?

But as I understand,you are not supposed to put unfinished compost in container.

Sierra,

If you are on the West Coast then you should be able to find fir bark easier than pine bark. Several people have recently posted about finding good quality bark in various locations along the West Coast. Someone recently found some EarthGro brand fir bark out West and it looked really good from what I recall.

Anything labelled as "forest products" I would avoid if possible. I do not know the exact definition of "forest products" but I suppose it could be anything (topsoil, moss, rotten wood, sapwood, bark, etc.) located in a forest and shoved into a bag. Who knows?

My personal definition of "pine bark fines" would be any material that falls through a 1/8" screen, so really anything between 1/8" and dust. That might not be what other people on the forum, including Al, consider to be "fines" but that's my personal definition.

The attached photo is heavily composted pine bark. This contains a high percentage of what I consider to be "fines" or fine material 1/8" and smaller.

Hope that helps.

TYG