100% leaf mulch this year - thoughts on deficiencies?

[solid7]

Originally Posted by drew51

But I see you're light years ahead of us all (yes, another Star Trek reference).

Not at all. If anything, I'm relying on time proven methods.

I screen out the unburnt lumps of wood, and soak them in the leachate from my worm bins for biochar. Burnt lumps server the purpose of acting as nutrient banks. Or, uncomposted/unsoaked biochar can also be used for carbon filtration for city water supplies. Again, all about using resources.

[Labradors2]

Originally Posted by drew51

I saw some references to recent studies and the leaves once composted are really not that acidic. Not acidic enough for say blueberries.
I would not assume just because you read it, or read anything it is correct. Of course if you applied that to this post, you could probably ignore it! What the heck do I know!

It's probably true that the leaves aren't that acidic "once composted". However, like bark chip mulch, while it is composting, it is tying up nutrients from the soil. Do we want to do that to our veggies?

I wonder how long those leaves will take to compost for the original poster. Hopefully, before he plants his tomatoes in the spring. I know they would take longer where I live because of our brutally cold winters. Therefore, I'd rather do it in a composter or away from my veggie garden.

As for the book, since it claims to be "A gardener's guide to the soil food web" (revised edition). I would hope that it would be correct (for what is currently known or assumed). Although our knowledge base is changing all the time and it's hard to keep up .

Linda

[solid7]

Bark chips do not tie up nitrogen in any significant quantity. Wood chips, yes. Bark chips, no.

[ScottinAtlanta]

Linda, I am wondering the same thing: "I wonder how long those leaves will take to compost for the original poster." In my compost pile, which is properly watered, greened, and turned, mulched leaves take 3 weeks to turn into black compost. In this mulch layer, in our climate of 40-50 degrees all winter, I am guessing 10 weeks. But I will just have to wait and see. If they don't, I will have to plant out with generous helpings of compost in the hole.

[carolyn137]

I received a PM this morning asking me to take a look at some of the last posts here and I have.

All I can say is that opinions of individuals are just that based on their own experiences and everyone should be respectful of opinions that are contrary to their own in a friendly and helpful manner.

Thanks in advance for your collective cooperation.

Carolyn

[drew51]

Thanks Carolyn for the reminder why we are here.
As mentioned I shred leaves twice. I use the lawn mower for one shred, or I have a blower you can reverse to suck leaves into a bag. Do that, then dump them and suck them up again. Shredded like this they will decompose faster, tend not to mat up either.
I don't have a compost area. I would have to sacrifice garden space for one. So I'm hoping the basic principles of lasagna gardening are sound.
Yeah since leaves are neutral when done composting no net change in PH appears to be the case.
Just to comment on that.

[Labradors2]

Originally Posted by solid7

Bark chips do not tie up nitrogen in any significant quantity. Wood chips, yes. Bark chips, no.

Interesting! When I think about it, wood chips probably "wood" take longer to decompose - and that's the kind that I get - in bulk - for my flower garden.

Linda

[drew51]

Originally Posted by Labradors2

Interesting! When I think about it, wood chips probably "wood" take longer to decompose - and that's the kind that I get - in bulk - for my flower garden.

Linda

A friend of mine Olpea has a peach orchard of about 350 trees. He said this:


I remember reading somewhere, something like 25% of the mulch by weight, actually becomes soil. The rest releases carbon back into the air. And since its by weight (and mulch is "fluffier" than soil anyway) it takes a long time to build a lot of soil with mulch. As I recall, an acre foot of topsoil weighs 3 mil. pounds. So to build, say, 6" of topsoil on an acre, it would take 6 million pounds of wood chips (1.5 mil X 4). More mulch than I'd ever want to shovel in my lifetime.

Another friend of mine manages about 10 orchards. Allan said this:


"... most of the problems you suggest about mulch don't often apply to fruit trees in my experience. Mulch on top of the soil doesn't decompose fast or evenly enough to cause N deficiencies in most soils according to research I've seen and my own experience. You need to incorporate it into the soil to get this affect.
If your soil I so deficient in N that the mulch takes it over the edge, their are a wide range of N sources to alleviate the issue. By the second season the mulch will probably be adding as much N as it removes as dying bacteria release soluble N. My guess is by the third, mulch will become a source rather than a sink- that is the created humus will more than compensate for fresh added mulch."

BTW these guys always look at research papers and such, and they depend on fruit to make a living. I highly respect their opinions. They come from experience. Allan has been an orchardist for over 35 years.

I wonder how leaves compare? I would think they break down a lot faster, so the cycles are accelerated compared to wood. Maybe adding some nitrogen with your leaves would help the bacteria, stop any leaching of nitrogen, and result the release of nitrogen eventually. Hopefully during the growing season.
You could probably build top soil faster with leaves.

[solid7]

Good info right there.

Even with the bark being incorporated into the soil, there is sufficient evidence that most barks - and particularly the coniferous types commonly used - do not contribute to a significant amount of nitrogen being tied up, to cause issue. There are even many potting mixes based on a large percentage of bark and bark fines. If inorganic methods are used, a fertilizer with higher than 10 of N are used, thus effectively offsetting it before it could even be seen. In organic methods, bark and bark fines are still used effectively. Ray Newstead's Earthtainer mix, is but one example. (which uses upwards of 30% pine bark fines with no regard given to organic or inorganic)

I live in an area with soil that is basically sand on top of finer sand. The yearly top dressing of mulch, or lasagna gardening, is my only real option for an organic land plot.

[AlittleSalt]

Originally Posted by Labradors2

Interesting! When I think about it, wood chips probably "wood" take longer to decompose - and that's the kind that I get - in bulk - for my flower garden.

Linda

This made me think about the wood I was picking up the other day. We have several acres that we let grow wild. When a branch falls - it is left there to rot (Unless it falls onto our walking paths). I picked up a couple branches the other day and what looks like dirt fell out from the inside when I broke the branches. The branches were the width of a Coke can. It was interesting.

[drew51]

In potting soils though the bark is always composted (check the bags). So fresh bark is a different beast.

[solid7]

Originally Posted by drew51

In potting soils though the bark is always composted (check the bags). So fresh bark is a different beast.

For commercial bagged potting mixes, that may be true. Sometimes I wonder if they do that to force you to buy more potting mix sooner. Al's 5-1-1 and Ray's Earthtainer mix, for example, do not require composted fines. That was initially the suggestion, but over time, it has seemingly been deemed to be unnecessary.

I use uncomposted pine bark fines in all my SIPs and containers. No issues. I use a 1:1:1 mixture of PBF/Peat/Perlite

Before I became convinced that the bark fines didn't need to be composted, I used to layer PBF and alfalfa hay in a large garbage can, and activate it with urine. To be perfectly honest, I haven't seen any difference in the composted and uncomposted, so I run with it... Other's mileage may vary.

[drew51]

Originally Posted by solid7

Al's 5-1-1 and Ray's Earthtainer mix, for example, do not require composted fines. That was initially the suggestion, but over time, it has seemingly been deemed to be unnecessary.

That's not true Al suggests composted bark. Or add nitrogen. I would think it would be hard to find anything but composted bark. Unless you stripped the trees yourself. Although I do agree with you. I doubt it would be a problem. It is slow to breakdown so nitrogen pull is slow.

I like a 3-1-1 mixture myself. But it really depends on uses. I don't always use perlite I use DE or combine perlite with calcinated DE. I usually add compost too, so a 3-1-1-1 mix. I think a living mix is best. I add fungi and bacteria also.

I use about 50 pots, so making my own is a lot cheaper!

[solid7]

Originally Posted by tapla

Partially composted conifer bark fines (pine is easiest to find and least expensive) works best in the following recipes, followed by uncomposted bark in the larger than 3/8" range.

Read more: http://davesgarden.com/community/for...#ixzz3MGz75wbN

That's from the man himself.

[drew51]

Originally Posted by solid7

That's from the man himself.

Right confirms what I said he suggests composted bark. Only to use uncomposted if that is all you can get. I think that is very clear. We happen to be friends. He lives nearby. We used to be at each others throats. We disagree a lot, but we eventually worked it out. We agree to disagree. I just talked to him a few days ago.