Why I Use Cover Crops
Being a co-owner of Botanical Interests means I can be creative with new products. Several years ago, we added a few cover crops in large-sized seed packets, hoping that gardeners would take advantage of this long-time, organic agricultural practice in their home gardens. Not only were cover crops a hit, they have also created so many conversations with customers wanting to know more!
Cover crops or "green manures" have gone hand in hand with agricultural practices for a long time and were even documented by the Roman poet, Virgil, in 29 BC. Cover crops naturally re-enrich soil, protect it from erosion due to rain or wind, improve its texture, and feed soil organisms, which maintain a healthy ecosystem in the soil, breaking down minerals and nutrients that feed plants. As gardeners, our success is directly tied to the soil in a very tangible way, but looking at the bigger picture, soil health impacts all its inhabitants and the greater environment.
"History is largely a record of human struggle to wrest the land from nature, because man relies for sustenance on the products of the soil. So direct is the relationship between soil erosion, the productivity of the land, and the prosperity of people, that the history of mankind, to a considerable degree at least, may be interpreted in terms of the soil and what has happened to it as the result of human use." - Hugh H. Bennett and W.C. Lowdermilk, 1930s
Can you tell I am passionate about soil?
Our current cover crop selection gives options for spring, summer, and fall cover crop growing. Any of the cover crops you choose to grow do two things: as they grow, they provide heavy shade, suppressing weed germination and growth.; and as they decompose into the garden bed or your compost pile, they contribute organic material.
Specifically, peas (sow in spring or fall), fava beans (sow in spring or fall) or crimson clover (sow in spring or fall) fix nitrogen (draw in nitrogen and convert it to a form that plants can absorb), trapping it in their roots for the next plants to use. Nitrogen contributes to the green growth of plants and is the nutrient we need to add most often in the garden because it easily changes to a gas and moves about. Buckwheat is excellent at mining the soil for phosphorus, which contributes to root, flower, and fruit growth, making it accessible to plants as it decomposes.
When I Use Cover Crops
In the spring, I sow crimson clover under my fruit trees to not only enrich the soil, but also to call in the pollinators, and, as a bonus, its strawberry-colored flowers are adorable and make great tea! In July, after harvesting my garlic, I sow buckwheat over the bed, chopping it down once I see about a third of it in flower (I don't want it to reseed), allowing it to regrow. I cut the buckwheat two or three times, letting the cut parts lie on the soil as a mulch, until I turn them in later. The bonus here, is that the bees love buckwheat flowers! Late in summer when my sweet corn or other warm-season crops are done, I sow fava or peas and oats in their place. A heavy frost will kill the peas and oats, but favas will keep going until it gets persistently cold (below 20°F). I let the dead vegetation stand until spring, shading the soil, which preserves moisture; the roots hold the soil in place and feed microorganisms over the winter.
I have even used cover crops in newly created beds, giving them some nutrition and keeping the weeds at bay while I decide what to sow. A healthy soil is a soil covered in something living. With few exceptions, a bare patch of soil will quickly be covered with vegetation which nurtures and protects it. Gardening with cover crops is a way we can pick beneficial plants to cover that bare patch rather than allowing weeds to take up residence.
"The soil is the great connector of our lives, the source and destination of all." - Wendell Berry, The Unsettling of America, 1977
Read more information on cover crops and how to choose the right cover crop for your organic gardening goals in our article, Cover Crops for a Naturally Better Garden.
Have you been using cover crops in your garden? Share your insight and experience in the comments below!