Green manure and soil improver
Purple vetch is an N-fixing legume that has positive effects on soil fertility, structure (loosening effect) and organic matter. It is beneficial in field crop rotation (Matic et al., 2008). In the USA, it is the most important green manure crop in rice fields (Williams et al., 2010). It was recommended to plough down purple vetch at flowering stage when it was used for green manure in vegetable crops, and to turn it under at the time of cereal sowing when it was used for cereal crops (UC SAREP, 2006).
Cover crop
Purple vetch has been reported to be used as cover crop in orchards, vineyards and cotton crops (Matic et al., 2008). It gives fair erosion control when the plant is well established, or in areas of natural reseeding. Control is better when purple vetch is mixed with grasses and grains.