We are here for an intervention.
Dark, luscious, fertile soil; weed-free, loose, loamy and teeming with life: This is the foundation every gardener dreams of starting each season with. Well-structured, full of nutrients, and wriggling with worms, an epic harvest with a minimum of effort awaits.
It’s remarkable how easy and how little effort it takes to get to this type of healthy soil, and the only thing standing between you, the gardener, and this paradisiacal plot is your toxic relationship with a petroleum-guzzling, oil-dripping, pollution-belching machine: the rototiller.
Fortunately for you, my friend, this column and I are here to have an intervention. An intervention is the correct term, because most gardeners’ reliance on their tiller is a similar reliance that drug fiends have with their substance of choice. Each time you use it, it gives you a short-term boost and perceived benefit, but comes crashing down inevitably. Each time you till, it appears you are making the soil fluffy and weed-free, but this is purely cosmetic and temporary. Tillers give you Barbie doll soil: cute to glance at, but offensive once you know what you are looking for.
Why not to till
Why till? To aerate the soil, many answer. As soil guru Elaine Ingham states, “When a tornado hits your house, it aerates [the shit out of] it. But now your going to need to spend the next couple of years rebuilding your structure.” In soil, the life is what builds and preserves the structure of the soil, and the tiller decimates both that life and the structure it builds. In addition, the action of the tiller releases both carbon and nitrogen into the air, diminishing the amount of nutrient reserves available for the plants that follow.
So if not to aerate, we surely must till to control and eradicate weeds, right? The exact opposite is true. Tilling churns up weed seeds from deep in the soil and brings them to the surface, the ideal location they need to germinate. So tillage is literally planting weeds in your garden.
Take a look at your existing garden beds as they emerge from their winter slumber. A surprising amount of microbial action takes place under a blanket of snow in our region, in fact more than perhaps any other time of the year. The microbes work hard to transform last year’s plant wastes into this year’s nutrients, and in doing their work they loft and aerate the soil and preserve that structure with bacterial glues and fungal mycelium. At my farm, our permanent beds have literally risen two to three inches over the course of the winter! They do this each year because we have never once tilled.
Smother love (with organics)
Are you ready to become adept at this no-till sorcery? Are you ready to have a healthier, more productive garden while also doing something great for the planet, all while working less? The key to all this magic is smothering your soil with love; love and organic matter.
If you have an existing garden, the easiest way to prepare for your spring planting is to smother your garden with leaves, straw or other organic matter. (Decaying leaves from last fall are the best choice; worms and fungi love them, and they’re free and seasonally appropriate.) In the spring, rake back this layer of leaves to allow the sun to warm the soil. After resting under this blanket of organic goodness, you’ll find the worms, microbes and fungi have completely devoured any crop residues, added fertility, and provided you with a beautiful seed bed ready to plant. It couldn’t be easier!
If you planted a fall cover crop or left last year’s plants in place rather than opted for the smothering method, you’ll need another strategy. While “turning in” is the traditional method, this can often result in a frustrating amount of re-growth from the cover crop we are trying to incorporate, or chunky bits of plants that haven’t broken down. I prefer to very shallowly turn my previous crops in, just barely cutting the roots under the soil surface and flipping, so as not to disturb my soil’s structure or expose dormant weed seeds. I then utilize the art of “occultation,” a word which means “to keep in the dark.” After turning in, I use a sheet of black plastic to cover the bed which prevents these freshly turned cover crops from accessing light. Making sure the soil stays moist underneath, a biological blitzkrieg similar to what occurs under the layer of leaves in the first method takes place. After a few weeks I remove the plastic and am greeted by a perfectly groomed seed bed, peppered with worm castings over the entire surface. Boss move.
If you are looking at creating a new garden bed from an existing lawn or weedy patch of ground, then smothering again is the answer, with an added dose of patience. This method takes six to 12 months, but once built is maintenance-free and results in an initial garden soil that many only dream of. This method involves smothering with cardboard and organic matter, and is a technique often referred to as a “sheet mulch.”
One common mistake when using this method is that many simply lay down dry cardboard and cover with six to 12 inches of wood chips. While this technique is often effective at suppressing weeds, it is also quite good at providing a home to rodents and breaks down quite slowly.
Time for a dance party
The key to building soil with a successful sheet mulch is to lay a thin layer of manure or compost on the ground first. Then, wet the cardboard thoroughly, mix a drink, crank the tunes, and have a dance party on top of it. This ensures the cardboard conforms to the ground below, eliminating habitat for rodents.
Then, rather than topping with wood chips alone, more manure, grass clippings, leaves, compost and other materials that break down quickly are piled in alternating layers, each one thoroughly hydrated. If you have enough material, add another layer of cardboard and repeat.
Top with a generous layer of wood chips to keep the rest of the materials contained, and to provide a pleasant surface to walk on. Keep this sheet mulch hydrated and within a year, all vegetation below will be completely smothered and digested. The sheet mulch itself will compost into soil and next season, you can plant directly into it.
James is a full time farmer, permaculture weirdo, and president of the OchO Society, a nonprofit dedicated to ecological education and adventure.