The Importance of Cover Crops for Your Garden

Want healthy soil? Plant a cover crop for a fall crop in your garden every year! Just because the gardening season has ended, it doesn't mean everything stops. It is important to maintain the health of your soil that has built up over the growing season. A healthy soil is the foundation of a productive garden, and cover crops can play a vital role in maintaining and improving this foundation. What's a cover crop? Simply put, a cover crop is any crop grown to cover the soil that can be tilled into the soil later to enhance soil health. Cover crops in your garden provide multiple benefits such as suppressing weeds, reducing soil compaction, increasing soil water holding capacity, and provide important nutrients to the soil. Let's look at some of these benefits, starting with weed suppression. Mother nature doesn't like bare soil. She will get back at you by growing something you don't want in any bare spot. Cover crops, like weeds, are quick growing and will shade the soil and compete aggressively with weeds and in some cases prevent weed growth. Their dense canopy reduces weed germination and helps lower weed pressure in your garden. The shade provided by the cover crops will also help control soil temperature, which benefits soil microorganisms. This in turn, increases microbial activity, which plays a role in nutrient cycling and soil health. Another benefit of cover crops and probably the most important, is the reduction of soil compaction. How many of us curse at how hard our garden soil has become over the winter? We've been taught how important it is to break up the soil for spring planting. We double dig and rototill to make it ready for planting. But what if we use cover crops to do most of that for us? The root systems of cover crops will create channels and pore spaces, reducing soil compaction. Radishes are perfect to use as natural soil aerators. I use Icicle radishes in my raised beds to prevent soil compaction, but for those of you with in ground gardens, or starting a new garden, Daikon radishes are perfect. Daikon radishes develop long, thick taproots (up to several feet) that penetrate through compacted soil. As the roots grow deep, they create natural channels, breaking up hardpan and improving soil aeration. By letting radishes decompose in place, aeration channels will remain, and nutrients will be released into the soil. This improved soil structure will allow better air and water movement in the soil, creating an environment for larger and faster growing roots of your garden plants. Along with radishes, cover crops contribute directly to soil fertility. Legumes such as clovers, vetches, and peas can fix atmospheric nitrogen, enriching the soil with a natural source of this essential nutrient. When radishes are allowed to decompose in place, the nutrients they release back into the soil include nitrogen, phosphorus, potassium, calcium, magnesium, sulfur and trace minerals such as zinc and copper. Not sure what cover crops to grow? A mixture of plants is best. You will find on the Internet several seed companies that sell pre-mixed packages of cover crop seeds that even identify their adapted hardiness growing zones. As you clean up your garden this fall, consider adding a cover crop to improve soil health, enhance garden productivity, and boost soil biology. John King is the current President of the Hancock County Master Gardener Volunteers. Master Gardener Volunteers are available to answer yard and garden questions by calling the OSU Hancock County Extension Office, 419-422-3851. Also, find us on Facebook at "Hancock County Master Gardener Volunteers."