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Leaf compost

Posted by jasoncoco (My Page) on
Wed, Feb 4, 09 at 12:45

Does anyone know what the ph of leaf compost might be, and if it is relatively high or low in its nutrient Content.


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RE: Leaf compost

I would think since the source of the compost being leaves, and leaves having a high nitrogen content, the resulting pH of any compost would also be acidic.
How high, one would have to get a test done.

Leaves are so available, the compost made would seem to be a good one for nutrition to many plants.
Its good though you are enquiring about the compost made from them.
Where such amounts cant be properly put into a compost bin, it is good still to save them by placing in bags, dampen them, poke finger holes in the bottom, and left behind a shrub or hedge for a year. The resulting leaf mold is great for roses the next summer.
If you can, chew them up before storage or placing in the compost bin for faster breakdown.


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RE: Leaf compost

Leaf compost is mildly alkaline, not acid. It can raise the pH of soil when applied on a regular basis. How much depends upon the soil itself, as well as other factors. Whether this constitutes a problem or not depends upon native pH of the soil as well as the plants being grown.

Leaves do NOT have appreciable amounts of nitrogen!

However, composted leaves do offer some direct nutritional value. How much would depend on the source of the leaves.
More important, however, is that compost adds huge benefits to the SOIL in terms of physical improvements and fostering that all-essential micro-herd. The more microorganism activity equates to improved nutrient availability and take-up by plants.

Does that make sense, jasoncoco?


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RE: Leaf compost

  • Posted by pt03 3 Southern Manitoba (My Page) on
    Wed, Feb 4, 09 at 16:44

Hi Jason

There would likely be variances on the nutrients and Ph of any compost so a hard and fast number may not be obtainable. When I had a similar question I found a fact sheet from Rutgers that I use (link below, click on download PDF). It gave me the numbers and variances I was looking for regarding nutrients in leaves. If one were to read the entire document it does mention a bit about Ph at the end.

I'm guessing this fact sheet refers to fall leaves versus green leaves as fall leaves are a strong Carbon.

Lloyd

Here is a link that might be useful: Plant Nutrients in Municipal Leaves


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More links

  • Posted by pt03 3 Southern Manitoba (My Page) on
    Wed, Feb 4, 09 at 16:51

Here is another fact sheet I reference to often. It makes sense to me and is easy to read and understand. Not saying it is the be all and the end all, but I like it.

Lloyd

Here is a link that might be useful: OSU Testing Compost


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RE: Leaf compost

Well the leaves are from a town that my grandmother lives near. She is a big gardener and has had a huge pile of leaves in her back yard since i can remember. The compost i am using right now is at the bottom of probably a 15 year old pile. its pretty old. She uses it all the time as potting soil without adding anything else. I try to add a little something most the time...Perlite, sta green potting soil and pine mulch. just a little pine mulch. Most of the mix is compost however. I am currently growing peppers in the mix and they seem to be nutrient deficient. So i was tryin to figure out if the compost has little nutrients or if the ph is wrong. I guess im going to have to get a ph soil tester. Thanks.


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RE: Leaf compost

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Feb 4, 09 at 18:31

Finished compost has very little in the way of nutrients. Try adding fertilizer.

Al


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RE: Leaf compost

Depending on which leaves you have the pH of those leaves, crushed just after they fall off the trees into distilled water, will measure between 3.2 and 3.8 on the pH scale. However after the bacteria work on them and covert then into leaf mold the pH will usually be in the 6.something range, nearly neutral. Compost will be just a little higher.
There is a significant part of our population that believes that compost has no nutrients, but many of us that have used nothing but compost to feed our soil then have to wonder why our soil tests show an increase over the years in the level of soil nutrients while those that pour synthetic fertilizers on there soil often show a loss of nutrients. The reason compost does not test high enough to be called a fertilizer is because the nutrients on that compost are bound and need the activity of soil bacteria to make them available to the plants.


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RE: Leaf compost

I have windrowed and composted leaves for years. Having water supplied by rain and seldom turning the piles I have found them to heat and compost to leaf mold in six to 18 months depending upon the makeup of the leaves in terms of species and also whether or not the leaves had been shredded. My land grant university offered cost-free soil tests in the past so I had a number of them tested for not only nutrients but pH. My resultant leafmold piles were always near neutral ranging from 6.8-7.1 in pH. The leaves are high enough in nitrogen to promote heating. One source that I've seen says that they have as much nitrogen as most barnyard manure, about one to two percent. I live in the mid-Atlantic region and many of the leaves are oak. I believe that the tannins that leach from the pile are acidic but the resultant product is nearly neutral. The end-product makes a great soil conditioner, imparts some nutrients and, as always, a gardener should have periodic soil tests performed to determine the exact nutrient levels within the amended soil.


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RE: Leaf compost

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Feb 5, 09 at 16:39

It could also be that ...... The reason compost does not test high enough to be called a fertilizer is not because the nutrients on that compost are bound and need the activity of soil bacteria to make them available to the plants, but rather because the actual nutrient level of finished compost is simply very low. They (nutrients) have to be there first - if they are to be eventually available - yes?

I didn't say it wasn't great for soil - compost is all I use on my gardens, with only a rare exception for a particularly needy plant. It appears that Jason is using it as the primary ingredient in a container soil, so supplemental nutrition will be needed to prevent deficiencies.

Al


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RE: Leaf compost

So Al how is it that the nutrient levels in my sandy soils has increased over the years with only compost and shredded leaves added, no "fertilizers", and why has the nutrient level of a friends sandy soil, who uses only synthetic fertizers, decreased over the same time period?


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RE: Leaf compost

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Feb 6, 09 at 9:01

We aren't talking about his/your garden. We're talking about a possible nutrient deficiency or unfavorable pH in a container soil "The compost i am using right now is at the bottom of probably a 15 year old pile. its pretty old. She uses it all the time as potting soil without adding anything else. I try to add a little something most the time...Perlite, sta green potting soil and pine mulch..." Obviously there is a difference between the total amount of nutrients accumulating from the tons? of compost you put on your garden year after and the gallon or two or three in Jason's container(s). The fact is, and the only point I made, is that the nutrient level of finished compost is very low and if he plans to use the composted leaf material as a primary ingredient in a container soil, he will need some kind of supplemental nutrition to avoid deficiencies. I'm not sure how there can be an argument about something so basic. ;o)

Take good care.

Al


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RE: Leaf compost

The reason compost cannot be called a fertilizer is because the nutrient concentration is extremely variable depending on raw ingredients and the quality/length of the composting process. To be legally termed a "fertilizer" and marketed as such, a product must be able to produce a guaranteed analysis of the NPK by percentage of total weight. That's pretty tough to do with such a variable end product :-)

No one is disputing that compost does not contain nutrients. But like any other organic source of plant nutrients, the concentrations are very low compared to any manufactured 'fertilizer'. That's just the nature of the beast. Its value to a garden is more in the organic matter, textural properties and hospitable environment it provides for soil organisms than in nutrient content, but in an inground garden setting, nutrient demands for established plants are rather low and generally easily satsified by applications of compost.

But because of the unique conditions and requirements of gardening in containers - an issue which seems to be getting overlooked by some responding here - any existing nutrients tend to be lost or diminish rapidly by leaching through frequent irrigation. It's a very unusual container plant that doesn't require supplemental fertilization for best results and annual crops and edibles tend to have rather high nutrients demands that make supplemental fertilizing a necessity for these types of crops in a container setting. Again, as previous posters have pointed out - for container culture - composted materials are neither the best medium nor the most reliable and efficient source of necessary nutrients.


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RE: Leaf compost

I use my compost in the containers wife plants in each year and with no supplemental nutrients added those plants grow and flower quite prolifically every year, far better than they did many years ago when she used a peat moss based potting soil.
Keep in mind that the only source of nutrients in the forest is the leaf mold created after the leaves drop and the soil bacteria have a chance to work on them. Tree leaves, and therefore leaf mold, are a very good source of nutrients for plants.


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RE: Leaf compost

  • Posted by pt03 3 Southern Manitoba (My Page) on
    Sat, Feb 7, 09 at 8:00

"Keep in mind that the only source of nutrients in the forest is the leaf mold created after the leaves drop and the soil bacteria have a chance to work on them.

Really? The "only source"? Are we sure 'bout that?

Lloyd


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RE: Leaf compost

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Feb 7, 09 at 9:57

Because someone gets a particular strategy to work, it should be no clarion call to the masses that seductively whispers, "Emulate me." It simply means that the individual making the claim is satisfied with the results and the claim speaks nothing of whether Jack or Jill might be satisfied.

The fact is, that no container soil - especially one comprised primarily of finished leaf compost will be able to supply the volume of nutrients required to prevent deficiencies w/o supplementation. If the compost is finished, it contains nearly nothing in nutrients (if you doubt this, look up the %s - and especially in available nutrients. If the compost is unfinished, it potentially has more nutrients available, but there is a greater risk of N immobilization (which of course would REQUIER supplementation to eliminate a deficiency - and that is only N!) and soil collapse as the compost continues to break down. It makes FAR more sense to use something structurally sound that won't compact as the primary ingredient in our soils.

If someone wishes to use leaf compost because of the conception it is somehow more organic than other organic soil components, or because it's in the back yard and free, I suppose you could understand overlooking other, better ingredients. That thought might be tempered though, by the musing that IF it was such a valuable ingredient in container soils, and BECAUSE it is obviously found abundantly at the lowest of costs (free everywhere), it should be used in huge volumes as either the primary ingredient in container soils, or at LEAST as a replacement for peat. I think that the fact it is not, speaks volumes; and, that though you may be able to 'make do' by using it in appreciable volumes in container soils, it is certainly not the best or most logical choice.

Al


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RE: Leaf compost

Thanks everyone for all your input. You all have been very helpful in helping me learn more about this particular subject.

Jason


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