Imagine a typical American farm. What do you see? Plowed fields! All those millions of acres of professionally farmed lands can lead us to believe that tilling is the best practice. Unfortunately, this is an example of conventional wisdom misguiding us. Large scale commercial farms destroy the soil through tilling, fertilizing and applying pesticides. The now unstructured soil blows away in the wind or washes away in heavy rain. As home gardeners, we can do better…. We can work with Nature to improve the fertility and structure of our soil by understanding the prime directive, which is to leave the soil alone!
No till farming is simply the practice of planting the earth with the least disturbance. Keeping the soil structure intact is critically important because healthy soil is an amazingly complex community composed of many thousands of species of inter-related organisms. This “Soil Food Web” works in concert with plants in an ongoing trade of nutrient commodities – Plants synthesize and provide carbohydrates for the soil microbes and the little guys reciprocate by producing nitrogen compounds that plants need. It’s a beautiful system….. Until someone flips it upside down!
A rich garden soil takes many years to develop. At first, fungi and bacteria aggregate soil particles and create the texture and structure necessary for good moisture and air movement. Once this structure is in place, more organisms move in, which increases soil productivity. What drives soil productivity is something called “nutrient recycling” which is really just a “poop loop” generated by organisms eating plant stuff, each other or each other’s poop…… You don’t need to think about this when you pick your gorgeous veggies!
Envision the soil as a metropolis like New York City. At the lowest levels of the city, there are pipes, wires and cables all intertwined in a million miles of intelligent tangle that actually keeps the whole system running somewhat smoothly (the fungi). Then there are the layers of beings: They catch rides through tunnels, on the streets and even up and down through vertical tubes (the bacteria). Some beings stay low all the time while others get close to the sky because that’s where they make their living! All of the big moving parts of the city are totally dependent on the beings and the intelligent tangle (the protozoa, amoebae, nematodes, arthropods and worms). Flip this city upside down with a giant shovel, or worse, roto-till it, and the intricately organized system is destroyed and most of the life with it.
So, how do you garden without messing with the soil? Here are some simple practices:
• Fertilizing – Adding a food source for the soil microbes can improve the living energy and productivity of your soil. Natural granular fertilizers (manure, animal or feed based) can be applied to the soil surface prior to top-dressing with compost. It’s important to cover with compost. Late fall or early spring are the best times.
• Composting – Top dress with compost to add diversity to the Soil Food Web and provide food and habitat for larger organisms.
• Planting – This is the easiest part. Once you’ve determined the proper spacing for your specific varieties, simply plant your seeds or seedlings with the least amount of digging possible. Any soil you remove from a hole should be spread at the surface and it’s always a good idea to top dress again with compost in the disturbed area.
After several years of the no till approach with consistent composting your soil should be naturally loose and aerated enough to plant with your bare hands.
Pete Bottomley, AOLCP
Coast of Maine Organic Products