Digging into Soil Health by Kassie Brown

All winter long I dreamed of spring planting. I purchased countless seed packets with big plans to grow organic soybeans to make tempeh, tomatoes to can, blue corn for cornmeal, cabbage for sauerkraut, and dry beans to last our small family throughout the next cold season.

I ordered 125 fruit and nut trees from the county tree sale and another 25 berry shrubs from an online planting stock store. We picked up seed potatoes, onion sets, and various crowns as we came across them. We drew maps of flower gardens and vegetable patches. We made calendars for succession planting. We planned. But deep in winter dreaming mode, we set aside the fact that as it was our first full growing season on our new 10-acre homestead, we had a lot of pre-planting work to do before any seeds could touch the earth.

Soil fungi and decomposing organic matter bind soil particles together to form aggregates. Aggregation in soils creates structure that allows air and water to penetrate deep into the soil profile.

We moved to this small farm in the early summer of 2019. The property is home to a large tobacco shed full of history, two sloping pastures thick with various agricultural grasses, goldenrod, invasive multiflora rose, and a good handful of other plant species alongside a steep bluff of overgrown woods. After many field walks, we determined that our main garden would have to go on the flattest section of a sunny, slightly sloped pasture north of the house. But before the crops could go in, we’d have to tackle the well-established pasture grasses.

Adventures in Creating Planting Spaces
As anyone who has ever tried to make a new garden bed where sod exists knows, creating new growing spaces is usually more of a job than anticipated. For us, the challenge of working tough sod was exacerbated by our goal to do as much by hand as possible. We did not want to till due to our knowledge of the connection between soil fungi—and the billions of diverse microscopic creatures who make their homes inside soil aggregates (clumps of dirt)—and healthy soil.

A plant root with soil particles attached as seen under the microscope. Plants pump out carbon-based foods through their roots to attract soil microbes such as a diverse range of bacteria and symbiotic fungi. These microbes exude sticky “glues” that help hold soil mineral and organic matter particles together. Living plant roots are critical for soil health and are key to preventing soil erosion.

We had made two 3’ x 30’ rows the previous fall using a deep mulching technique popular in the permaculture world. To do this, we first mowed the grass, spread a thin layer of compost, and topped two layers of cardboard with a mixture of hay/straw/wood shavings and goat manure from our barn. The plan was to smother existing vegetation while creating a nutritious in situ compost for our crops of choice the following season. Unfortunately, due to our relatively heavy clay soil and rainy climate, the sheet-mulched beds became water-logged and did not look like the friendliest environment for baby plants come spring. If we were going to become successful homesteaders and get our corn, beans, potatoes, and squash planted, we were going to need throw in the towel and do some digging.

Choosing Not to Till
Tilling the earth is a common practice in our culture. It’s mostly regarded as a necessity and considered good for the soil. It “fluffs” the soil and “lets the air in,” some say. Many farmers claim that tillage helps the soil warm up faster in the spring. Others just know how hard it is to deal with unwanted plants without a sharp blade and some horsepower. True as these things may be, tillage is a type of combustion, and just like other forms of combustion—such as the burning of wood, coal, and gas burning—it blows off large amounts of carbon.

Within soil, carbon is the queen of the food chain. Through photosynthesis, plants suck carbon dioxide out of the air, and then transform it into food (carbon being the backbone of all sugar, carbohydrate, and protein molecules). Significantly, a lot of the “carbon food” produced by plants is pumped underground through their roots, leaked out into the soil, and fed like a delicious restaurant buffet to billions of beneficial underground creatures such as fungi, bacteria, and their food-chain predators, protozoa and nematodes.

Collectively, these microorganisms “pay” for their carbon buffet by offering the plant soil nutrients like calcium, magnesium, and phosphorus—nutrients that the plant would otherwise be unable to access without these tiny, hungry microbial partners. From this perspective, it’s easy to understand plants for what they truly are: high-tech carbon pumps transferring atmospheric carbon below ground to feed a vast and complex soil microbiome. Since microbes survive on the carbon-food buffet provided by plants’ roots. Keeping a plant thriving is the #1 job of soil microbial communities. An intact soil ecosystem makes our jobs as farmers and gardeners so much easier.

Mushrooms in the garden or lawn are excellent indicators of soil health. They break down organic matter and feed plants through the mycelium-root connection.
All of the animals at Potter Ridge Farm—such as the farm’s “strong-willed” goats seen here—are pets. Although goats are technically browsers, they also enjoy grazing the fresh grasses and weeds around the farm. The farm’s animals also provide a key ingredient for healthy compost: manure.

In this microscopic circle of life, after being eaten by plant-partnering microbes, carbon becomes part of the soil food chain locked inside the bodies of fungi and bacteria until they are eaten by larger organisms like protozoa and nematodes. Carbon is also stored in massive molecules condensed by fungi and bacteria, called humic and fulvic acids. Once in the soil, carbon becomes humus, the component responsible for a soil’s “good tilth.” It helps the soil hold water while also promoting good drainage through its resistance to compaction. As humus, carbon acts like a magnet for soil micronutrients and also houses the beneficial creatures that partner with plants to ensure the health of entire ecosystems.

Unfortunately, tillage causes carbon to be burned off from the soil and released back into the atmosphere through a rapid injection of oxygen (aka, combustion). Tilling soil also rips and shreds the beneficial microbes that plants desperately need in order to obtain full health. Tillage creates bare soil, which is prone to compaction by rain and erosion by wind and water, which further destroys habitat for these tiny plant partners.

Back to our first-year garden beds. I desperately did not want to till them. But I also saw little choice if we were to get our seeds in the ground. We ended up purchasing a broadfork which is a strong, human-powered tool that pries up sod without the added impact of a gasoline engine. It’s hard work, but it allows me to observe the impact of my tillage. As I remove clumps of grass, I can see the delicate white strands of mycorrhizal fungi intertwining with the grasses’ root systems in an ancient exchange of carbon and earth elements. I can create a garden bed but leave some soil clumps as a reservoir for microbes. Hopefully, after this one event of soil destruction, I can plan a rotation of cover crops that will be winter-killed in order to leave a relatively clean bed for spring planting.

A rainbow arcs brightly over Potter Ridge Farm. Solar panels were mounted on top of the old tobacco barn. The barn’s timber rafters used for hanging tobacco to dry are still in place. The new solar panels give this historic structure a warm welcome into the 21st century. The panels provide all of the couple’s energy needs during the day and feed the grid with extra electricity produced.
Pip, the couple’s pet pig, helps siphon food waste from the compost pile.

Compost: The Bedrock of Sustainable and Organic Agriculture
Tilling or broadforking one time in the creation of a garden from sod has one benefit: It allows me to work in high quality compost. Compost is the bedrock of sustainable and organic agriculture; it’s the starting point in any conversation around food as medicine. Compost is the bridge between death and new life. When made well, it is rich in humic acids (condensed carbon-based molecules full of earth elements). Good compost is chockful of diverse microorganisms engaged in a constantly cycling micro-food-chain that produces an abundance of plant-available nutrients, and even plant growth hormones.

A common misconception is that compost is compost is compost. We have just one word to describe an incredibly complex process of recomposition. The quality of compost is determined by many factors: starting materials, water quality and quantity, oxygen availability, pile size, temperature, etc. In my opinion, despite these variables, compost is always best when made close to its source and end point. In a backyard or even porch setting, small batch compost can be made with a tumbler or by an ambitious person with a pitchfork. Good compost needs a delicate balance of carbon and nitrogen, commonly referred to as “browns” (carbon) and “greens” (nitrogen). The general idea is that smelly things—like food scraps or fresh grass clippings—should be surrounded by non-smelly things like brown leaves, wood chips, or cardboard. Good compost is made with enough water, but not too much. Compost should never be dripping, but it should also never be dry. It requires plenty of oxygen, which is why turning is so vital. Experimentation is key when it comes to producing your own backyard compost. The finished product should be fluffy and crumbly with a color that matches a bar of chocolate with 70 percent cacao. And it should never smell bad. Bad smells are always a sign that your pile needs more oxygen, and/or more carbon.

Across the Earth, from farm field to backyard, our soils are in need of some TLC. There is a whole universe below-ground.

We are just scratching the surface of our understanding. No matter how much soil you have to work with, building healthy soil is one of the most important things we all can do to support biodiversity, pull climate-changing carbon from the atmosphere, better infiltrate water, and scale back the use of chemical inputs. Incorporating well-cared for, “70 percent cacao,” forest-scented compost to new garden beds is the best way to create a thriving soil biome that will support your plants for years to come. Get growing!