Wednesday, September 7, 2011

No machine needed: Worms do the tilling

Welcome to Microbe Rich ("M R") gardening

"I'm never going back to my old way of gardening!" My neighbor recently said to me. "Building the soil the top down makes much mores sense. My garden was so much more productive and easier to maintain. I did almost no weeding this year!" She thanked me profusely for showing her my method of gardening, which requires no mechanical tilling.
Spring garden—no mechanical tilling needed
            For the past two years I watched my neighbor diligently till her garden, and then struggle with weeds, plant disease and nutrient-related issues. At first, I remained quiet.
I typically don't suggest new gardening methods unless someone asks for my advice. Gardening is good, no matter what methods people choose, so I won't critique or try to convert until they ask. It's important that people find the gardening system that works best for their personalities, work styles, schedules and local surroundings.
I am not a gardening purist. My agricultural mentors are so diverse that I borrow concepts and draw tips from a wide variety of methods, including Lee Reich's Weedless Gardening, EliotColeman's Four Season farming, Ruth Stout's no-dig method, Patricia Lanza's lasagna gardening and John Jeavons' Biointensive mini-farming. I don't follow any one of these philosophies to an absolute T, but instead pick and choose what makes most sense for my location, goals and values.
Straw mulch on garlic
I admit—my spine does shiver like someone ran fingernails down a blackboard when I see a tiller break open ground. I can't help but want to protect the soil structure—the key to good tilth (the soil's physical condition). Healthy soil is the foundation of the Earth's health—and therefore our health—on so many levels.
But I remain quiet until people ask.
So was the case with my neighbor, until she repeatedly exclaimed about the quality of my produce and beauty of my garden. How do I do it? She wanted to know.
It all boils down to soil tilth, I explained. A simple test with a digging fork showed her the impact of tilling. When I drove the fork into her garden, the prongs barely sunk so that they were only halfway underground.
Then we walked across the street to my garden. My foot barely exerted any pressure as I pressed the fork into the soil, and the prongs quickly disappeared underground. I then lifted the dirt with the fork, careful to not to disrupt the soil layers as I did so. The moist soil fell off the fork in small loose clumps.

While the first couple of inches of humus are the most nutrient-rich soil layers, many vegetable crops like to grow long roots to capture water and minerals well below the surface, I explained. "Mechanical tilling compacts the soil, so that the roots can't grow deep," I said. Moreover, tilling lifts buried weed seed to the surface, so they are more likely to sprout, adding to garden labor.
Leaves on edamame and popcorn
Most importantly, a no-till gardening method keeps soil structure in place. A well-structured soil provides many ecosystem services. Water percolates under the surface without disrupting nutrient-rich topsoil. A healthy population of microorganisms in the decomposing organic matter turns the soil's abundant nutrients into a form that plants can uptake. The healthy, intact soil system combats disease more easily and provides habitat for predators of garden pests. I could go on…
In general, a garden becomes easier to manage when we work with our ecosystem rather than disrupt it. So to take care of my soil, I follow the guidelines below when creating a garden system.

Layers of cardboard, composted manure, straw and grass clippings
1) I start new garden beds in the fall by layering cardboard, manure and other organic matter on the area to become the garden. The grass blades and roots underneath the cardboard decompose along with piles of organic matter so that the soil is rich and easy to work in the spring. The decomposition process takes at least three months and is best done in the coldest time of the year.
2) In the spring, I loosen the top 12-inches of soil with a digging fork, and if I'm direct seeding, I'll break up the clumps further with a hand tool until the soil is fine. This process is not labor intensive if enough organic matter was added (the amount required is dependent on the soil's clay/sand consistency) and has decomposed properly. The clumps should fall apart easily.
Broadfork (A simple digging fork works too)
3) Unless I've just seeded a bed, it is always covered with mulch—most often grass clippings or leaves. As my beds mature, I add perennial cover crops for a permanent green manure.
4) I continue to add organic matter to the soil throughout the season, whether that be compost, cover crops or comfrey leaves, depending on the plants' specific requirements.
5) My beds are permanent. I never walk in my garden beds, but instead on paths mulched with wood chips surrounding the garden.

To be precise, plenty of tilling is going on in my garden. I've created the ideal habitat for worms to thrive, and they in turn aerate the soil, which is the key action of tilling. Oxygen stimulates the activity of microorganisms to release nutrients to the plants.
I should also clarify that it is possible to create good soil tilth even with tractor tilling. But I have only observed that on farms with specialized equipment and a skilled mechanical farmer.
For us backyard gardeners, some cardboard and mulch will do the trick, and in the meantime, the plants love all of that organic matter and produce flavorful, high quality fruits and veggies.

Follow this blog and the M R Gardens Facebook page for growing tips and advice on low maintenance no-till systems. You can also hire Megan to help you design a garden system that fits your lifestyle and needs, set up a management plan, and work with you in the garden. Set up an appointment with Megan by calling 828.333.4151 or emailing gardens@wncmretc.com.