Aternative to sheet mulching

I'm starting to steer away from classic sheet mulching for a number of reasons.

1. It can imbalance the soil by bringing in lots of potassium relative to other nutrients.
2. It can create a fungal dominated soil; some plants don't like this.
3. It is a lot of work, and some benefits are over hyped.
4. It can provide a haven for the wrong kind of critters.
5. Importing organic matter over the long term is inherently unsustainable.
6. Without fossil fuels, many of these materials, such as waste straw and especially wood chips, will become less available.

What I'm working on instead is developing a system where a dense cover crop, such as rye, is grown over the winter, and then smothered by rolling a tarp or other sheet stuff (even cardboard) over it. The sheet would be removed and stored for next year after a month or so, leaving a mat of dead stems and roots as mulch for the next year or so.

Any opinions?

Is there a particular reason you want a mulch versus simply having plant cover (dense polyculture)? I think in cases where sheet mulch is not a good idea, mulching with finished compost and then growing a dense plant cover might be the best (or good anyway). Using finished compost versus mat of dead stems etc prevents critter haven.

This is a fairly large scale community farm, with mostly annual vegetable plants. Composting is difficult here, and is also a lot of materials handling, which it would be good to avoid. We need something to cover the ground during the winter and spring, before the plants cover it. Also, spacing a little wider reduces competition for water.

In my home, permaculture garden, I'm going the compost, light mulch, and dense planting route, though I am importing some mulch to get things started.

I think you'll always risk the critter haven problem with any kind of sheet mulching, including your rolled cover crop. Here the main critter problem is sowbugs/pillbugs, and they only seem to go after seedlings if they don't have enough moist rotting plant material (aka mulch) to nibble on. So the best mulch for here seems to be chop and drop, but that might be bad news in slug territory.

Re-Seeding every year doesn't seem sustainable.
Sheet mulching for annual gardens has been mentioned as unlikely to work long term.
I have found it to be great, in my raised beds, but I haven't used it in any in ground setting.
Using a sheet good to cover things temporarily seems like a great idea to me.
I have used scraps of Hardboard in direct contact with the ground, it is surprisingly durable, an doesn't use glue to hold it together.
Its the same stuff used in whiteboard, peg board, and clipboards.

Why wouldn't reseeding be sustainable? Especially if I grow the seeds. But I've never heard of a gardener yet who didn't buy at least SOME seeds!

Its the buying of the seeds.
Because I am lazy and cheap, I like self seeding or perennial plants. Cover crops are usually killed off before they go to seed, but I guess that one could wait, if reseeding was desired.
I also LIKE importing biomass in the form of other peoples yard wastes, Autumn leaves in particular.
It always feels like someone threw out bags of money by mistake, and I just make of with them.
Most of the materials I bring home are carbon heavy, is that what makes it potassium rich?

I thought the whole point of sheet mulching was a way to deal with weeds. It allowed you to make the soil more fertile and yet not be overrun by weeds.

As an example, I am about to add in a 50' run of metal fencing in an area that is infested with weeds, so I am going to lay down cardboard right over the weeds and then mulch on top which will allow the plants I want to grow to thrive without competition.

In the other thread about the horrors of sheet mulching, it seems that what the guy laid down wasn't done in a way to break down so all he did was create habitat for rodents and other pests.

Growing a cover crop and mowing it down in the chop and drop style isn't that much different than sheet mulching.

All these things are tools, not holy grails. The land I am working has about 6 inches of dirt (NOT soil) and then hardpan so I need to add lots and lots of organic matter to create rich soil. So sheet mulching allows me to bury the weeds seeds AND prevent the weeds from growing through the barrier all while I make the soil richer. If I had rich soil I would just be tilling in last years mulch or just planting right on top of it and never do sheet mulching again.

Michael Bushman wrote:I thought the whole point of sheet mulching was a way to deal with weeds.

For me the point of sheet mulching is to protect and feed the soil. I don't have much in the way of weeds.

Tyler Ludens wrote:

Michael Bushman wrote:I thought the whole point of sheet mulching was a way to deal with weeds.

For me the point of sheet mulching is to protect and feed the soil. I don't have much in the way of weeds.

Then what does the "sheet" do in sheet mulching? Wouldn't what you be doing is just mulching?

Maybe that's what I'm doing, just mulching. In a big area, which I consider the "sheet" - so maybe I don't even know what other people think of as "sheet mulching"! I think of "sheet mulching" as meaning "mulching a broad area" as opposed to "spot mulching" which would be just mulching around a specific plant such as a tree.

What do other people mean by "sheet mulching"?

Tyler Ludens wrote:Maybe that's what I'm doing, just mulching. In a big area, which I consider the "sheet" - so maybe I don't even know what other people think of as "sheet mulching"! I think of "sheet mulching" as meaning "mulching a broad area" as opposed to "spot mulching" which would be just mulching around a specific plant such as a tree.

What do other people mean by "sheet mulching"?

laying down a *sheet* of cardboard, board, newspapers overlapped, so that a solid weed barrier is formed, at least temporarily. a good thick layered *sheet* before adding the mulch/soil/etc on top of it, will holds the weeds at bay for 1-4 years or so.
it also will kill off all the top growth of the ground/lawn, under the sheet so that those plants feed the soil.

everything has pros and cons. just using deep mulch or any kind of mulch are also critter habitat, that is definitely one of the cons of using a lot of mulch.
the benefits are substantial though.

i find its harder to direct seed in that situation, new seedlings are attacked the worst, but older established plants go in ok. unless those underground tunnelers get them!

well i am pro sheet mulching, deep mulch, and thats pretty central to my gardening methods.

i agree with the previous poster who said that if they had better soil, it would be less important to import organic matter. using deep mulch, which usually requires me to import something, even if its not from very far away, like local wood chips...is the only way i can grow anything close to a conventional kitchen garden....

i cant personally make enough compost, or mulch -though now more and more am starting to get enough living mulch/plant bio mass/chop and drop to feed the soil and build up on the deep mulch. i rarely, if ever use fertilizer, so i got to get the momentum going somehow, to get the soil rich enough to grow regular type crops.

I always thought the sheet in sheet mulch referred to the layers of different materials. Each separate layer was a sheet, like a layer when you make the bed. It's possible that I don't understand the difference between lasagna gardening and sheet mulching.

I would like to throw out another approach.
Planing a cover crop in the fall is a good idea in many cases.
But what about planting a dense cover crop in spring that cannot take the heat and will die off in the heat of June or July.
I tend to grow a number of peppers, egg plant, tomatoes, etc in pots until the soil temp is around high 70's.
I have found that I have a bunch of spring weeds that will grow, seed and die off when temp get about that range.
So why not develop a weed the will grow, seed, and die so you can plant your hot season crops?

Casie Becker wrote:I always thought the sheet in sheet mulch referred to the layers of different materials. Each separate layer was a sheet, like a layer when you make the bed. It's possible that I don't understand the difference between lasagna gardening and sheet mulching.

Yep, that's what I thought also. Maybe I'm confusing sheet mulching with sheet composting. I guess maybe what I was doing was sheet composting, not sheet mulching. I don't use cardboard.

Gilbert Fritz wrote:I'm starting to steer away from classic sheet mulching for a number of reasons.

1. It can imbalance the soil by bringing in lots of potassium relative to other nutrients.
2. It can create a fungal dominated soil; some plants don't like this.
3. It is a lot of work, and some benefits are over hyped.
4. It can provide a haven for the wrong kind of critters.
5. Importing organic matter over the long term is inherently unsustainable.
6. Without fossil fuels, many of these materials, such as waste straw and especially wood chips, will become less available.

What I'm working on instead is developing a system where a dense cover crop, such as rye, is grown over the winter, and then smothered by rolling a tarp or other sheet stuff (even cardboard) over it. The sheet would be removed and stored for next year after a month or so, leaving a mat of dead stems and roots as mulch for the next year or so.

Any opinions?

I think in your circumstances that could work. I could also recommend a living mulch cover crop seeded with your winter rye or whatever you decide to make your dense biomass producing cover.. Something like maybe a nitrogen fixing low growing clover? Once the rye is killed back by either mowing or knocking down (a roller crimper works great for this) then the clover could provide ground cover that still is alive and producing photosynthesis. (which feeds the soil food web)

Maybe a variation on these two, but modified to fit your circumstances?

Permaculture living mulch playlist

In my case I still use sheet mulching, but substitute sheet mulch for the black plastic in the above closely related systems. This way I get the best of both. I mulch a strip in sheet mulch, and let the permaculture perennial plants survive between strip mulching rows. It solves the problems with sheet mulching you mentioned because it uses 1/3rd less mulch material but yet provides good mulch coverage for just the annuals you plant. Also becomes sustainable because you could use the growing cover crop as your mulch material. You could import mulch, or you could simply grow your own. Another slight variation I am experimenting with is trying both ways, making the beds in the same place each year, or moving them over into the aisleways each successive year in a rotation. Just to see what works best in my local conditions.

TO:     Gilbert Fritz
FROM:     Eric Koperek = erickoperek@gmail.com
SUBJECT:     Alternative to Sheet Mulching
DATE:     PM 7:32 Tuesday 2 July 2016
TEXT:

(1)     Broadcast Dutch White Clover (Trifolium repens) at 12 to 14 pounds per acre into standing vegetation.

(2)     Mow grasses & weeds immediately with a sickle-bar mower to cover and protect clover seeds.

(3)     Irrigate immediately or wait for rain.

(4)     When Dutch White Clover reaches its mature height of 6 inches the ground is ready for planting.

(5)     Use a common lawn mower to prepare a strip for transplanting.  Alternatively, use garden shears to clear spots for planting.

(6)     Set transplants directly into living mulch.

(7)     Use cut clover to mulch around transplants.  Mulch gives transplants time to put down roots.

(     Irrigate immediately to help transplants grow new roots.

(9)     Remember to fertilize and irrigate both crop and living mulch.  Apply dilute soluble fertilizer in irrigation water.

(10)     Keep ground covered with Dutch White Clover year-round = 365 days annually.  No plowing, disking, harrowing, or cultivation will be necessary.  Clover will kill most weeds by shading.

(11)     Any weeds that grow above the clover canopy should be thinned, not eradicated.  Ideal weed spacing is about 1 weed every 3 feet or approximately 5,000 weeds per acre.  Weeds provide food and shelter for beneficial insects necessary to protect crops.

(12)     For large fields, mow clover then use no-till transplanter.

(13)     To grow maize, mow clover as close to ground level as possible (1 inch high) then immediately sow corn with a no-till seeder.  Mow again 2 weeks later when corn starts emerging from the soil.  On rare occasions a third mowing may be needed 2 weeks later.  Adjust mower height to avoid cutting maize seedlings.  Irrigate and fertilize generously to encourage growth of both corn and clover.  

(14)     Planting into a living mulch of Dutch White Clover works best with transplants or large-seeded crops.  Small seeded crops like carrots and beets require much more effort.

(15)     To grow small seeded crops it is necessary to kill narrow strips of clover.  Mow first then use a flame weeder to clear rows for planting.  Use a no-till planter to deposit pelleted seeds.  Flame weed just before seedlings emerge from the soil.  Check fields daily for crop germination.  Flame weeder will keep rows weed free.  Dutch White Clover will prevent most weeds from growing between rows.  Hand thin any weeds that grow above crop or clover canopy.  Ideal weed spacing is 1 weed every 3 feet or about 5,000 weeds per acre.  Widely spaced weeds will not significantly reduce crop yields.

(16)     You can manage entire commercial vegetable farms using nothing but Dutch White Clover, lawn mowers, and no-till equipment.  For best results irrigate and fertilize fields regularly to encourage maximum growth of both crops and clover living mulch.

(17)     Planting into Dutch White Clover living mulch is the easiest and least costly way to grow commercial vegetable crops or home gardens.  

(18)     Planting into living mulches is not a new technology.  The practice dates back to the Renaissance (about 1500) in Holland and other European countries.

ERIC KOPEREK = erickoperek@gmail.com

end comment

 

If your soil is already rich in organic matter, then laying that heavy layer of mulch down isn't as necessary as it is for us who were given heavy clay with next to no bio-life in it.

Yes, sheet mulching brings all sorts of critters to the party.  In my experience, after a few years 90% of the soil biota is positive.  Worms by the millions are the most obvious, but the entire soil food web is driven by carbon.  

Sustainable?  Well --- there are hundreds of things we are currently doing that are not sustainable, but we do them now so that when peak oil arrives (if it hasn't already), you will have already improved your land to the point where you don't need fossil fuel imputes.  Using earth moving machinery, for example, to dig swales, ponds and other earthworks might be argued to be unsustainable, but in the long term, once you've established your earthworks, you'll never need to do it again.  As for the sustainability of wood chips and cardboard, yes -- perhaps in 100 years there will no longer be these resources.  Or will there be?  I don't know, but I do know that the guys who are hauling truck loads of wood chips to the dump from my neighborhood are more than thrilled that I save them a trip to the dump.  And the cardboard is just sitting there in the card board dumpster right near where I park my truck at work.

Cover cropping is very sustainable. Keeping a living crop on soil for protection is a good thing.

Soil will continue to improve over time. That is what we all want! the different crops have different root systems that form underground and the different crops bring about differing results.

In a recent video i saw a demonstration where they grew different cover crops in a field. The result was ,  The more different seed mixed together -the better the result.

North Dakota farmer went from 2 inch water penetration to 10 inch in 10 years. That is extremely impressive on that windy clay land.  You have a good plan.