In moderate climates, farmers cultivating organic produce often use winter cover crops to add soil organic matter, improve nutrient cycling and suppress weeds. Now, thanks to research conducted at the U.S. Agricultural Research Station in Salina, Calif., these producers can optimize cover crop use by refining their seeding strategies.
ARS horticulturist Eric Brennan conducted studies comparing winter cover crop planting protocols in organic systems along California's central coast. He planted rye using three seeding rates of 80, 160 and 240 pounds per acre. The seeds were either planted in a grid pattern or in traditional rows. All seeding was carried out in October.
Brennan found that planting rye at higher seeding rates consistently improved early-to midseason rye biomass production and weed suppression. But he saw no consistent crop improvement from grid planting. Brennan also studied seeding rates and planting patterns using a cover crop of legumes and oats. Results were similar to the rye cover crop research.