Cowpea, aersatile legume for hot, dry conditions

Cowpea is one of the most ancient crops known to man, with its center of origin and subsequent domestication being closely associated with pearl millet and sorghum. Now it is a broadly adapted and highly variable crop, cultivated around the world primarily as a pulse, but also as a vegetable (both for the greens and the green peas), a cover crop, and for fodder. Cowpea has a number of common names, including crowder pea, blackeyed pea, southern pea, and internationally as lubia, niebe, coupe or frijole. However, they are all the species Vigna unguiculata (L.) Walp., which in older references may be identified as Vigna sinensis (L.). The largest acreage is in Africa, with Nigeria and Niger predominating, but Brazil, West Indies, India, United States, Burma, Sri Lanka, Yugoslavia, and Australia all have significant production. Dry seed production is estimated at 1.24 million tons annually.

In the U.S. the largest commercial application is for types most frequently marketed as blackeyed pea which are harvested and then sold after cleaning (dry). In the Southern US there is substantial production of a variety of cowpea types, which after drying are sold to processors. These processors essentially cook and soak the dried product, to make it ready to heat and serve. These products may be either canned or frozen, and are referred to as a group as Southernpeas. This name probably derives from the common use of shelling the pods green and then cooking the peas fresh, similar to the common peas. The focus within this guide will be on production of dried blackeye pea, which can be harvested with conventional grain combines.

Cowpea is considered more tolerant to drought than even soybeans or mung beans, due to its tendency to form a deep tap root. By nature the plant is a vine, hence the best breeding opportunities for modem agriculture systems is with the more determinate and bush types, although for forage or cover crop applications the vine characteristic is preferred. There is a fairly active breeding program throughout the primary production areas, which include the Southeastern U.S., Arkansas, California, and Texas. Yield information is available on the varieties released from these programs.

California produced 90% of the U.S. dried cowpea in 1994; a total of 42,000 tons was produced in the U.S. that year. Dried blackeye pea has averaged from $0.23 to 0.43 per pound from 1982 to 1994.