Permie Orchard : Let's talk plastic mulch

Hi Stefan - really enjoyed your DVD. This is information that really deserves to be spread more widely.

Your use of plastic mulch is probably going to cause some raised eyebrows in this forum You discuss how earthworms pull organic matter underneath the plastic through the small openings made for companion plants. Still, it seems there could be much more active soil life without the plastic. Can you discuss some of your experiences with other systems that finally convinced you to use plastic?

Patrick Mann wrote:Hi Stefan - really enjoyed your DVD. This is information that really deserves to be spread more widely.

Your use of plastic mulch is probably going to cause some raised eyebrows in this forum You discuss how earthworms pull organic matter underneath the plastic through the small openings made for companion plants. Still, it seems there could be much more active soil life without the plastic. Can you discuss some of your experiences with other systems that finally convinced you to use plastic?

Patrick raising eyebrows has always been a good thing. Let me begin by saying i was TOTALLY against plastic in agriculture. What I realized was that I was against FILM PLASTIC. The flimsy one season plastic which is a huge waste of a resource. I understand WHY they use it but it's still a waste. Install, one season and pull up. Ridiculous. We use the thickest plastic available, usually 6 mil plastic. This plastic will last the life of the orchard (40-140 years!!) and be recyclable when done or be useable in another orchard (since the holes are already there!).
We started the orchard with mulch. 6'' of wood chip mulch and shredded leaves, 2-3' wide. Do you realize how much mulch you need to do one acre of planting in this way??? After spreading 30 trailer loads we figured we were done for 2-3 years. Mulched in december just before the snow. By may the next spring we could not see any more mulch!!! Our years of using aerobic compost tea made our soil so alive that in 6 months the microherd ate through all our mulch, under the snow. By June we could not find our trees since the grass was taller than the trees. Do we find and apply more mulch? What do we do? Our trees did not grow the first year due to the grass competition. So we had used plastic in the nursery for 4 years with great results, one quick weeding per year and we were done for the season. We decided to go with high grade plastic. It has turned out to be our best investment for the life of the orchard. We do 4-6 hours per acre per year of weed and plant (when we weed we replace it with a more desirable plant). Huge time saver. For the grassy lanes we go with a motorized version of chop and drop we call mow and blow. And that it. Raise your eyebrows and keep on weeding while I take a NAP.

In the UK it is possible to get a biodegradeable mulch sheet that takes 3-5 years to break down. This lasts long enough to let the trees establish without grass competition and avoids using plastics. It might be worth looking to see if something similar is available where you are.

Katy Whitby-last wrote:In the UK it is possible to get a biodegradeable mulch sheet that takes 3-5 years to break down. This lasts long enough to let the trees establish without grass competition and avoids using plastics. It might be worth looking to see if something similar is available where you are.

True Katy if you WANT it to degrade. I don't want it to degrade as it saves me a LOT of work long Term.

Stefan, how about a geotextile tarp?

The fibrous stuff? I'm still pulling strands of black plastic out of beds, soil, compost etc... decades after the previous people laid it down. Once it starts to break down it is a total nightmare, and stops doing it's job.

Hugo Deslippe wrote:Stefan, how about a geotextile tarp?

Hugo I have seen the woven UV stable geotextile used successfully in a vineyard. Seems to last well and work well for them, also lets water through.
I have not tried the fabric ones.

Michael Cox wrote:The fibrous stuff? I'm still pulling strands of black plastic out of beds, soil, compost etc... decades after the previous people laid it down. Once it starts to break down it is a total nightmare, and stops doing it's job.

Your correct Michael, the key is to buy the one that will not break down, recycle it someday but not one that breaks down.

I like the idea of the plastic mulch, but I'm concerned about the massive amount of water needed for irrigation. We don't all live next door to a lake. I'm actually surprised there isn't more conversation around this topic.

I have found that I need much less water when I use plastic mulch. It stops evaporation.

Does the plastic mulch you're suggesting cause a super hot area just below it that could threaten to sterilize soil microbes in the top bit of soil with hot conditions, or make poor conditions for worms? Is there a second layer of an organic mulch on top of the plastic? (Sorry - have not seen the video yet.)

I guess chop and drop mulch would just decompose on top of the plastic, and nutrients from decomposition would drift down to the edge of the black plastic over time, or into the holes around the trees, and the trees' root zones would eventually be out beyond the plastic to collect those nutrients mined by the comfrey or nitrogen fixers?

It's good to hear that it doesn't get too dry underneath, due to condensation. That would be a concern of mine as well.

I so want to be idealistic and use just wood chips and cardboard (what I do on 20 tree scale), but when contemplating a larger-scale project, I'm concerned about results, because there is a lot more risk in involved in the money and time commitment for a big project - so I'm strongly considering using plastic mulch.

Rob

From Stefan's Facebook page:

"Yes we have perpetual rights to the water in the lake next door. Was one of the clinchers to buying it in the first place. We pump 60 gallons per minute for 3 hours per day to water 12 acres."


Rob: he talks about worms and the plastic in the movie. Nature's coping skills are somewhat surprising sometimes. You'll just have to watch.

Stefan Sobkowiak wrote:We use the thickest plastic available, usually 6 mil plastic. This plastic will last the life of the orchard (40-140 years!!) and be recyclable when done or be useable in another orchard (since the holes are already there!).

What type of plastic are you using that will be resistant to breaking down, for 140 years of UV, in a 6-mil thickness. That sounds like a tough job. I am not sure I can imagine ANYTHING that fits that spec.

Thank You Kindly,
Topher

@Topher - Most of the plastic is pretty well shaded by leaf drop and the tree canopy above, so it's probably not really getting hit too hard with sunlight. If it was direct sun, I'd agree - I've never had plastic last more than a season or two in direct sun (even 6-mil black stuff). That being said, there is a plastic they use for hoop-style greenhouses lasts about 10 years in full sun, 365 days a year. I suppose they could make a black version of that. It's also much stronger and thicker.

Erik Lee wrote:@Topher - Most of the plastic is pretty well shaded by leaf drop and the tree canopy above, so it's probably not really getting hit too hard with sunlight. If it was direct sun, I'd agree - I've never had plastic last more than a season or two in direct sun (even 6-mil black stuff). That being said, there is a plastic they use for hoop-style greenhouses lasts about 10 years in full sun, 365 days a year. I suppose they could make a black version of that. It's also much stronger and thicker.

10 years is a long way from 140 years, and still usable.

Rob Read wrote:Does the plastic mulch you're suggesting cause a super hot area just below it that could threaten to sterilize soil microbes in the top bit of soil with hot conditions, or make poor conditions for worms? Is there a second layer of an organic mulch on top of the plastic? (Sorry - have not seen the video yet.)

I guess chop and drop mulch would just decompose on top of the plastic, and nutrients from decomposition would drift down to the edge of the black plastic over time, or into the holes around the trees, and the trees' root zones would eventually be out beyond the plastic to collect those nutrients mined by the comfrey or nitrogen fixers?

It's good to hear that it doesn't get too dry underneath, due to condensation. That would be a concern of mine as well.

I so want to be idealistic and use just wood chips and cardboard (what I do on 20 tree scale), but when contemplating a larger-scale project, I'm concerned about results, because there is a lot more risk in involved in the money and time commitment for a big project - so I'm strongly considering using plastic mulch.
Rob

Good concern Rob. Your absolutely right about 20 trees. Yes use cardboard and mulch and enjoy the great results. On an acre or 5 acre scale that no longer is very practical.
The year of adding plastic you want a period of 2 weeks of hot and killing since we lay plastic right on sod (long time sod) and grass does not want to die without a fight.
The extra heat and especially humidity does a great job of transforming the grass into a wonderful fungal layer (like after the meteor impact theory) that would make Paul Stamets proud. Lifting the plastic after 2 weeks and seeing an absolute cover of mycelium feeding on the decaying sod is heartwarming.
Then we begin to mow and blow the sod of the grassy lanes onto the plastic. A little grass mulch goes a long way to keep the plastic cooler. So we use the heat to our advantage in the beginning and then we minimize it with a mulch layer.
Yes the mow and blow (mechanized chop and drop) adds a mulch layer on the plastic which becomes a rich compost that encourages seed germination. The nutrients flow into the holes as you guessed, giving very happy plants in the holes. We were amazed today at our 2'tall chive plants that had bases that looked more like onion stalks than chives. I won't spoil it all for you since you have not seen the film. I can suggest you wont regret if you buy or recycle the best plastic (silage bag plastic is the best you can get and often for free!!!) Just go pick it up and cut it to size. We used this to make sure we wanted to use plastic, then bought it in rolls. Best of success on your project.

How long has plastic been around? 140 years is an astounding amount of time to contemplate plastic surviving.

Topher Belknap wrote:

Stefan Sobkowiak wrote:We use the thickest plastic available, usually 6 mil plastic. This plastic will last the life of the orchard (40-140 years!!) and be recyclable when done or be useable in another orchard (since the holes are already there!).

What type of plastic are you using that will be resistant to breaking down, for 140 years of UV, in a 6-mil thickness. That sounds like a tough job. I am not sure I can imagine ANYTHING that fits that spec.

Thank You Kindly,
Topher

Topher after 3-4 years as Erik says the trees, shrubs and associated plants should be creating more and more shade. Plus the mulch on the plastic provides more shade. Most of the plastic is not exposed to much sun. We have had plastic on for 7 years with no sign of any kind of breakdown and it will just get more covered with time.
We have already put our poultry on parts where the mulch was so thick that sod was forming. The poultry scratched it up, even scratching the plastic with no problems. I presume the 6 mil plastic you refer to was not UV stable and likely for indoor use as sheeting.
Granted maybe not 140 years but certainly the life of the orchard.

The way weeds are growing lately you have me thinking about this. Plastic would require irrigation even in the rainy season wouldn't it?? Or is there a way to allow water to run through plastic, to some degree? I have found rainwater awesome for plants. My high ph well water not so great, I think.

The "weed mat" type plastics let water through the weave. You can control the water on poly through earthworks underneath (keeping contour, etc.) and making small slits where you want it to drain through. You can put a small piece of plastic as a second layer there to suppress weed growth, or a mulch basin.

Think of it as a sealed swale or terrace.

steve temp wrote:The way weeds are growing lately you have me thinking about this. Plastic would require irrigation even in the rainy season wouldn't it?? Or is there a way to allow water to run through plastic, to some degree? I have found rainwater awesome for plants. My high ph well water not so great, I think.

Yes Steve you could just use plastic IF you have enough holes with enough plants, like 1 hole per 2 ft2 minimum AND you dimpled the surface ie created an indent around each hole so the rain would run into the hole and not away from it. Your right the volunteer plants are really growing as we get to the longest day of the year. We have not weeded the orchards yet just mow and blow. In the next 2 weeks we will do a round of weed and plant and weed and seed, 5 hours per acre max and done for the year.

Trying to wrap my head around the earthwork configuration, R Scott mentioned. The best I can think of might be 2 swales one slightly up hill from trunk and one below. (not much level ground here). Both with slots for living mulch and drainage cut.
Also wondering if Fire ants might enjoy the plastic shelter?
I would think this would really cut down on the area to be mowed also. Never liked mowing, just a lot of hard work, money and resources down the drain.

steve temp wrote:Trying to wrap my head around the earthwork configuration, R Scott mentioned. The best I can think of might be 2 swales one slightly up hill from trunk and one below. (not much level ground here). Both with slots for living mulch and drainage cut.
Also wondering if Fire ants might enjoy the plastic shelter?
I would think this would really cut down on the area to be mowed also. Never liked mowing, just a lot of hard work, money and resources down the drain.

Good point Steve. If we turned the gas used to mow into plastic so we would not need to mow as much the plastic ends up being a Carbon neutral or even Carbon positive solution.

I wonder if the alfalfa in the alleys would be defeated by 6 mil plastic...

Ann Torrence wrote:I wonder if the alfalfa in the alleys would be defeated by 6 mil plastic...

Ann my question is why would you want to defeat the queen of legumes in the alleys. It is just benefitting the trees in the rows. Alfalfa is the deepest rooting legume we have and I presume you have as well. Usually down to the water table after 3 years. Then nothing stops it. It can be mowed 4 times in the summer and creates a great mulch. The animals love to graze it, especially the fowl. We use a mechanized version of chop and drop we call mow and blow. When the grass and alfalfa is more than 12" we cut it with a sickle bar mower, we can leave it in place or let it dry for 1 day and them mow and blow it. If it's less than a foot high we usually just mow and blow so the chop goes under the trees.

I'd run a test on the water distilling off the plastic, all kinds of nasty leaching. I don't even trust food grade plastic let alone some rated to last so long. This in my opinion could never be called organic.

Stefan Sobkowiak wrote:
Ann my question is why would you want to defeat the queen of legumes in the alleys. It is just benefitting the trees in the rows. Alfalfa is the deepest rooting legume we have and I presume you have as well. Usually down to the water table after 3 years. Then nothing stops it. It can be mowed 4 times in the summer and creates a great mulch. The animals love to graze it, especially the fowl. We use a mechanized version of chop and drop we call mow and blow. When the grass and alfalfa is more than 12" we cut it with a sickle bar mower, we can leave it in place or let it dry for 1 day and them mow and blow it. If it's less than a foot high we usually just mow and blow so the chop goes under the trees.

Stefan,

I somehow missed your reply. Since I wrote that comment, we have ordered our mower! We have been using a Grillo 2 wheel tractor and sickle bar, but it's too much to keep up. I am thinking about some plastic down the rows to conserve our irrigation water, not really between the rows. The alfalfa is legacy, we did nothing to discourage it when we planted the trees, and it grows fine even with no water, the bees love it. It's staying-I can't imagine getting rid of it anyway. But we'd like to grow some other stuff too

If you are still reading this thread, what's the Canadian position on animals in the orchard and food safety? The USDA/FDA regulations can be interpreted to mean that they have to come out of the orchard 90 days before harvest. Because <sarcasm> after all the salmonella and listeria incidents in our food supply (which comes from industrial packing lines) we can't have chickens crapping in the orchard </sarcasm>. Absolutely no understanding of the traditional Normandy apple/dairy systems, etc. Like an American politician of the 1990s, I am working the semantics, "what does 'in' mean, exactly?"

Does anyone know what this plastic is specifically called or what search terms to use to find it? I have come across some black films in rolls but I am not certain if it is the correct type of plastic and long lasting.

I like the idea of a plastic mulch in the initial stages of setting up an orchard but once the trees get large enough to compete better with grasses and other natives would probably want to remove it. I don't drink from plastic bottles and it just doesn't feel right to leave it there long term if it could be leaching. Not really sure if there are any other viable options for a large orchard though that would save the amount of work plastics will.

I think if you put in a swale system with your trees on or just below the downhill mounds with plastic, the swale would still work to help hydrate the soil. Thoughts?

It's called plastic mulch. You can find it from suppliers of 'plasticulture'. We used 4 mil (which is 4 thousandth of an inch thick). It comes in different widths rolls. We expect it to last the life of the orchard (30-50 years). As for the leaching from plastic it usually happens in the first few months so using a thin film like 1 mil, as is used for vegetable production, leaches out during the season and again the next and the next with successive new plastic mulches. Using a thick one mulches in the first few months and no more in the following years. It's a choice, I chose work saving with the mulch. If you have less than 100 trees go with organic mulch and reapply it every 1-2 years. If you have more than 100 trees and want to go with organic mulch invest in a mulch spreader. There are good ones that fit in orchard rows.

Stefan Sobkowiak wrote:It's called plastic mulch. You can find it from suppliers of 'plasticulture'. We used 4 mil (which is 4 thousandth of an inch thick). It comes in different widths rolls. We expect it to last the life of the orchard (30-50 years). As for the leaching from plastic it usually happens in the first few months so using a thin film like 1 mil, as is used for vegetable production, leaches out during the season and again the next and the next with successive new plastic mulches. Using a thick one mulches in the first few months and no more in the following years. It's a choice, I chose work saving with the mulch. If you have less than 100 trees go with organic mulch and reapply it every 1-2 years. If you have more than 100 trees and want to go with organic mulch invest in a mulch spreader. There are good ones that fit in orchard rows.

Thanks for the feedback Stephan and help finding the appropriate plastic. I definitely agree with saving as much labour as possible.

Are larger trees better able to compete with grasses and weeds? Does it depend on the rootstock? I am in Alberta and so far my research has me leaning towards standard rootstocks.

A short remark: I go to the plumbers supply store you get loads of huge cardboard boxes folded neatly.

Angelika Maier wrote:A short remark: I go to the plumbers supply store you get loads of huge cardboard boxes folded neatly.

Good to know and may come in handy for some smaller areas on my property. Personal gardens etc.

My long term plan is for 5-10 acres of orchard as one of our main income sources. Labor and infrastructure cost is a huge consideration at this scale. I'm really intrigued by Stephan's model. I haven't seen his video yet but will be purchasing it soon. He seems to have struck a good balance between business considerations and what would be environmentally ideal.