Green manures are fast-growing plants sown to cover bare soil.
The foliage of some green manures (E.g. Mustard) smothers weeds and their roots prevent soil erosion. Many green manures are Legumes which are plants able to ‘fix’ Nitrogen from the atmosphere. When dug into the ground while still growing, green manures return nutrients to the soil and help improve soil structure. Green manures are often used in the vegetable garden to provide a valuable source of natural plant food for the next crop.