Cover crops generally refer to either:
1. growing plants between two main crops, generally during the winter or summer. Cover crops are sown after the main crop has been harvested and before the next crop is sown. They cover the soil during the intercropping period, preventing erosion and nutrient loss as well as limiting weeds.
2. using your main crop or pasture phase as a green manure crop and returning all biomass to the soil as opposed to harvesting (normally returned at, or just prior to flowering)
Cover crops add organic matter and boost biological activity. Cover crops can also be used to fix nitrates in the soil to limit leaching.
