Planted primarily to manage soil quality.
Cover crops are crops that are planted primarily to manage soil fertility, quality, water, weeds,pests, biodiversity, and diseases; rather than to grow produce. They are often used in sustainable agriculture as a more natural method of maintaining the quality of the growing area.
Example cover crops include clover (fixes nitrogen) and sorghums & mustards (both suppress weeds).
Use this tag for all questions cover crops - especially whether they should be used, and which should be used for your particular situation.