Soil Building Basics 4: Keep Roots in the Ground
There is nothing in the whole nature which is more important or deserves as much attention as the soil. Truly it is the soil which nourishes and provides for the whole nature, the whole of creation depends on the soil, which is the ultimate foundation of our existence.
~Friedrich Albert Fallon
German scientist, 1862
Plants roots anchor the soil in place. They help soils resist erosion from wind and flooding as well as resisting drought. Roots provide homes for microbes physically, but plants also actively feed microbes at their roots by exuding sugars through their roots to feed microbe populations in exchange for compounds the plants can't make on their own. By keeping living roots in the soil for as much of the year as possible, you are actively supporting this underground soil-building world!
There are many ways to keep roots in the ground to feed soil microbiology. One simple strategy is for leaving the roots in the ground at the end of the season by cutting back the tops and leaving the roots in place. Even dead roots still provide structure and can continue to "feed" the soil a carbon source as they decompose. I like to "weed" this way during the season by cutting annual weeds to the ground, chopping up the "tops" if they haven't gone to seed and spreading the chopped leaves and stems as a mulch on the soil surface. This is a great way to grow your own mulch whether intentionally (with intentional plantings) or unintentionally with weeds.
Here's what it might look like to intentionally keep roots in the ground while planning for a continual harvest:
Another way to keep roots (especially living roots) in the ground for as much of the year as possible, is to choose perennial plants when possible. Perennials are plants that come back again and again for multiple seasons. Edible perennial plants are particularly fun! Many cultures from around the world use perennial plants as staples in their diets. Commercial agriculture has a tendency to focus on annuals: think of corn, wheat, potatoes, tomatoes, sunflowers, or canola ... all wonderful crops, but they must establish themselves in a single season from seed. Because perennials come back each year they have energy stored in their roots which allows them to produce much earlier or later in the season. They are able to take better advantage of sunlight throughout the year and this also allows some of them to produce in conditions that would be too stressful for annuals (too wet, too dry, too cold, too hot or too shady). Think of asparagus spears in early spring or fiddleheads, perennial sorrel greens or ramps coming up as soon as the snow melts in temperate forest woodlands or fields. Think of perennial chile bushes (chiltepins), cactus fruits, and mesquite bean trees in the southwestern United States. Perennial edibles can complement annuals and grow in places or in ways annuals can't, allowing you to maximize the food a piece of land can produce.
Perennials can be used even in your backyard as windbreaks, buffers on the edges of wet areas to anchor soils in place or help with drainage, or inbetween garden rows or crops on a slope to stabilize an area or as a pollinator hedgerow. Replacing mulch with living groundcovers is yet another creative way to keep living roots in the ground. Some groundcover examples might be wild strawberry (edible) or prairie clover (nectar source) or common heal-all (medicinal and preferred by some endangered bumblebees) or sedums (hardy, drought resistant) or creeping thyme (tasty herb). Think about where in the landscape you can intersperse perennial alternatives that you don't have to plant again each year and that might help maximize your harvest or wildlife support throughout the year.