Designing the Right No-Till System for Your Farm
There is no one perfect universal no-till system. Full stop.
Deep compost mulch may work well in one place—or scale—and not so well in another… and not for certain crops. No mulch at all, perhaps, or cover cropping, or a hybrid system may make more sense depending on your context—climate, soil, materials, et cetera. There are an almost incalculable number of factors that go into designing a no-till system that you must weigh. That is what the video below was all about.
But, after making the video, I decided—hell, let’s really dig into this thing—let's dissect all the different considerations that should go into this decision. At least, all that I can think of. I’m sure as soon as this is posted I’ll think of more. Let us know if we’ve left anything out. Keep in mind there is no order to this—no one single consideration necessarily trumps another. All of these factors must be digested at once as they are all of relatively equal importance. So, eat up!
Climate
There are no lack of ways in which your climate could easily affect the way you can or should go about your no-till system. The parts of the climate that are most relevant to this are your average temperatures and your average rainfall. If you live somewhere cool, for example—say zone 5 or below—straw or hay mulch may not be the best option for you, especially in the Spring. This may keep the soil too cold to get in early enough, or could delay the biological activity in the soil that comes with warming, which negates one of the big advantages of no-till. Perhaps cover crops—some that winter kill, and some that need crimping—could work better. Or maybe it’s a deep mulch compost system.
However, your average rainfall may necessarily narrow that down a little. If you regularly get ~1” rainfall at a time or more—events that could essentially cause some erosion on deep compost mulch (which may cost you money, expose weeds, and/or reduce the efficacy of the system)—that will play a role in designing your style of no-till. Right now, I’m describing most of the Eastern US and Eastern Canada—our rain events can be pretty intense, especially lately.
Cover crops or even heavier mulches like straw and/or leaves may be more effective in environments prone to heavy rain. And, if it’s a cold climate with heavy rainfall, or you’re looking to get a head start in Spring, tarps could be employed as an immovable mulch (until they end up in the tree line, thanks wind) while heating up the soil. Prep in the Fall, pull back in the Spring, and plant your heart out.
Editorial note: Jackson, of StoneHouse (zone 6, KY), tarped beds in the Fall for early Spring production to prevent erosion, warm the soil, and keep it dry enough to plant. For late Spring/early Summer, ground was sown to rye and crimson clover in the Fall and tarped early Spring (with the tarps just removed from early Spring plot). Spring beds are ready to plant this week and the cover crop in the next block appears to be breaking down ahead of schedule. So far, so good!
Soil-Type
Soil type may determine not which no-till style you are able to use but WHETHER OR NOT you are able to use certain approaches, at least initially. For instance, a heavy clay soil may prevent you—at least at first—from going without a deep mulch compost. It may require a substantial one-time tillage to inject a nice dose of microbial life and organic matter (if so, remineralize your soil while you’re at it) or a good chiseling to break the hardpan. Deep roots will do this over time, but if you’re already doing an initial tillage, make a pass with a chisel. Heavily rocky soil might also require a deep compost layer (or straight-up rock removal). Sand has its own issues with allowing too much drainage, so building a compost layer or, again, “injecting” some compost in via a one-time tillage may help retain nutrients and moisture. Compost is a great conditioner for clay, many people use peat for sandy soils. All of that said, deep mulch has benefits for all soil types, given it meets your other criteria.
Given time, the goal is to balance the soil physically, chemically, and biologically. The ground used for production will undergo a slow (or fast, if you’ve got the upfront capital) transformation into a more amenable soil. So, begin with an approach that is appropriate for your soil type and topography. Pay attention, first and foremost, to the physical properties of the soil, your cation exchange capacity, and get your macro nutrients (N, P, K, Cal, Mg) balanced to begin with. Then, move onto the micro/trace elements. Keep in mind the four principles we outlined in the beginning.
Material Availability
If your climate, soil, crops, and scale all point toward a mulch-based system AND/OR you simply have a lot of available carbon lying around, there is the possibility of having at least part of your operation mulched. However, you may decide against, maybe against your own will, and it may be better to grow your own cover material, buy a durable ground cover, or some even go without and keep the soil planted in cash crop as much as possible.
Back to mulch. But, which mulch? Well, it’s important that you look around and see what’s you have access to… for cheap. In California they may have rice straw whereas in the Pacific North West, it may be wheat straw or hay. Here in Kentucky, we love our horses, so manure and compost are abundant. That may not be the case in Tasmania (is it? I know nothing about Tasmania—feel free to send info... or plane tickets). Extension agents can be a great resource here for tracking down what makes good/cheap mulch for your region and probably know exactly where you can find some, as well.
The quality of your material may be important, too. Just because we can get a lot of compost and manure doesn’t mean it’s nice, fine, and fluffy (ours ain’t, but it’ll do). A lot of cheap straw from someone who isn’t 100% sure if there are rhizomes grass seeds in it—but, meh, it’ll be alright—may not be worth the gamble on a commercial op. Always, always, talk to the source to make sure there’s nothing in it you don’t want on your farm, or at least know what you’re getting into.
Last, you may be in a place—like podcast guest Stephen of Buena Vista Gardens in Hawaii—where compost and bulk materials are hard to come across or really expensive. There’s always a durable ground cover, like woven fabric, especially useful (and reusable) for crops that will be in the ground for long periods of time. Or, you may decide to keep your production area in cash crops for as much of the season as possible to act as a ground cover.
Crops
Speaking of cash crops… your crop selection will ultimately effect your style of no-till, especially with regard to keeping your ground covered.
Baby greens production, as well as most direct seeded crops, will simply require a nice seed bed. No way around it. If you plan to lean heavy on baby greens, be prepared to back off the mulches almost entirely. Many baby greens growers we’ve spoken with do soil balancing—adding minerals, fertilizers, and maybe a small amount of soil conditioner to improve the texture—at least where they are going to be growing these crops. They simply do not till, fertilize, replant. There is no mulch to speak of. Transplanting is a different matter. If you rely heavily on transplanting, covering the soil with something in the meantime is much easier. Get creative, go bananas, tell us what interesting new mulch systems you come up with.
Have a multitude of different crops? Well, you can also have a multitude of different no-till styles (at least if you’re good at crop planning). Block crops based on specific mulch needs. Obviously, you have options (like Frith’s winter kill pea/out cover crop method), but your crops will determine what you use. Or, you can pick a no or low mulch system, just keep the soil covered with something. If you have access to decent, fine compost, a deep mulch system may be possible, too. Remember, it is always all about your context.
Scale
What works on 1.5 acres may not work on 10 or 20 (still looking for you 10+ acre no-tillers out there). At least, not economically. When you’re working on that scale, you may have to pick a system that is more adapted to your machinery (or conversely, pick machinery that is more adapted to that scale and the system of no-till).
That said, if you’re looking at large scale production there is no reason you could not use a deep mulch system, but the reason that works so economically on a small scale is that those beds are being used multiple times in a given year. So, if you did 10 acres in deep compost mulch, you would need to make sure they are constantly in production to make it viable. Otherwise, that would not work out economically, even if you found an economical way to make/buy/spread the compost. Also, on that scale, the environmental concerns grow with that much phosphorous. Keeping it planted then becomes a duty, which is why the cover crop/roller crimper method seems to make the most practical sense.
Cover crops are much more economical on large sale, but they require a fairly high degree of technical execution. I still believe we have yet to see all—or even half—of the large scale techniques, though, and I plan to explore them in depth as they develop.
As always, if you have any thoughts or concerns or question or additions, please let us know!