Buckwheat

With its wide, heart-shaped leaves and rapid growth, buckwheat is the best green manure crop for weed suppression. Widely used for building worn-out soils as it accumulates phosphorous, potassium, calcium, and nitrogen, making all these nutrients available to the next crop. Its fibrous root system improves soil aeration and friability, encouraging earthworm activity. Plant after danger of frost in spring, or plant 40-60 days before the first fall frost; leave it to winterkill, then plant directly into it in the spring. Seed at 45-90#/acre or 2#/1000 sq. ft. Organic.