General description and special characteristics – Cowpea is an indeterminate, drought-tolerant, bushy annual that is useful for forage and as an edible pulse. A native to central Africa, this legume can be used as a green manure and is a good control for soil erosion due to its rapid growth. Cultivated cowpeas in Asia are of three types: grain, vegetable (yard-long bean and bush sitao), and fodder. The grain and fodder types are prevalent in India, while the vegetable type is prevalent in China and Korea. It is a major component of traditional farming systems, normally planted after rice is harvested from paddies.
- Chiang Dao – A viney cowpea with pods approximately 20cm (8in.) long and vines shorter than 1 m. It takes four months to grow to maturity, and fixes approximately 80kg N/ha.
- Lahu/Mae Ai – A bush variety with a grayish seed that shows good resistance to disease.
- Samoeng – A short, creeping vine with black seed. Often intercropped with upland rice, its plump pod is considered better tasting than the Lahu variety by ECHO Asia Seed Bank staff.