I’ve harvested the cabbage and broccoli, and dug the potatoes and garlic. I’ve brought in buckets of beans, crates of cucumbers and wheelbarrows full of watermelon. My once lush and fruitful garden suddenly has vacant space.
After the intense growing season I actually enjoy the look of bare ground, but leaving space unoccupied in the off-season, from October to April, misses an opportunity to improve soil for the next growing season. Cover crops feed soil, improve soil structure, restore nutrients and suppress weeds when my garden is off-duty. They are a sustainable alternative to commercial fertilizers and herbicides.
Cover crops feed soil. All cover crops add organic matter to soil. Microorganisms eat the organic matter and release valuable nutrients back into the soil for plants to eat.
Cover crops improve soil structure. Root penetration aerates the soil, adding air and increasing water and nutrient absorption. Cover crops help hold soil in place during the winter, guarding against unwanted erosion. In spring the cover crop is tilled into the soil, alleviating compaction and preparing a nice plant bed.
Cover crops restore nutrients to soil. Plants eat nitrogen which can leave soil depleted at the end of the growing season. Legume cover crops like vetch and clover add nitrogen to the soil. Non-legume cover crops like rye, oats and wheat, reduce leaching losses of nitrogen and other critical nutrients.
Cover crops suppress weeds. Cover crops shade out weeds by robbing them of valuable sunlight and inhibiting their growth.
Rye, oats and wheat are my favorite cover crops to plant in fall, but there are several legume and non-legume cover crops to choose from. Cornell University’s online cover crop guide offers a free selection tool to help you choose the best cover crop for your farm and garden. The comprehensive guide provides detailed information on each crop, including seeding rates and spring removal instructions. Access the guide at http://covercrops.cals.cornell.edu/.