Yellow Trefoil (or Black Medic) is ideally suited as an intercropping or undersowing green manure. This trifoliate species is a particularly shade tolerant legume which can be successfully established under tall standing crops to help suppress weeds, retain soil moisture and build soil fertility.
Yellow Trefoil is often used for under sowing brassicas, beans, potatoes or any other canopy forming crop.
Surface or shallow sow just before or as the main crop is becoming established. Keep the soil moist to aid germination. When undersowing Trefoil on occasion become too tall and should therefore be cut back to avoid unwanted competition with the main crop.
Once harvesting has taken place, cultivate the remaining green matter into the top soil along with any other mulched aftermath or leave on the surface to protect the soil over the winter season.