Answer: For a winter vegetable garden cover crop, you might prefer an annual and let it die in place and cover the soil surface because these are among the easiest to work under in the spring in a home garden situation. An alternative would be to cover it with a generous layer of straw and/or chopped leaves late this fall and then work that into the soil next spring.
Mail order sources for seed for different cover crops would include Pinetree
and Johnnys Selected Seeds
Good luck with your cover crop!
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