From the good people at the Tilth Producers of Washington and Nash's Organic Produce: Cover cropping is a method used by organic growers to increase the biological activity and health of soil. A critical tool for soil fertility management in any size garden or farm, cover crops are fabulous nitrogen fixers and are an integral part of the natural cycling of nutrients.
When planted in the fall, cover crops hold nutrients that are otherwise leached away in the winter, while protecting the soil surface from erosion. If used in the spring and summer, cover crops are ideal for fixing atmospheric nitrogen and building the soil's organic matter. If your soil is particularly poor, begin cover cropping in the spring and apply two to three rounds, ending with a final planting in the fall (mid-September to early October).
- Gardeners should use about 10 pounds of seed to cover crop 500-700 square feet.
- Plant 1/2-1 inch deep and water as needed. If soil is not too wet, the seeds will germinate in cold soil, so cover crop seed can be planted in the cool spring.
- When it is mid-calf height, turn the cover crop in with a space or shovel, inverting the top two inches of soil.
- 2-4 weeks after turning it in, the cover crop should mostly be broken down, and you're ready for a second round, or to plant your garden. Allow more time in the spring for the rye/vetch to break down. The ease with which it breaks down is directly related to its height, so don't let it get too big before you turn it under.
Find a cover crop seed blend of rye and vetch at Nash's Organic Produce at Ballard Farmers Market.