Hairy Cowpea (Vigna luteola) is a common native edible vine that occurs most commonly in disturbed areas around fresh and brackish wetlands, and in flatwoods. At the ELC it can be found at the edge of the brackish marsh on the upland side of the dike where it grows with companions like Carolina Willow, Pond Apple, Green Buttonwood, Limewater Brookweed, and Sawgrass.
Hairy Cowpea was introduced to the African continent as a cultivated bean (also known as hemerochory) where the flowers and roots are often eaten raw or cooked. Eaten raw, the flower tastes like beans and has a slightly bitter aftertaste. As a plant in the Fabaceae, or pea family, it produces small 2mm long edible beans that can be cooked alone or together with the seedpods.
Hairy Cowpea can easily be confused with the Eastern Milkpea (Galactia volubilis), which also occurs on the ELC campus but usually in disturbed coastal uplands. Eastern Milkpea has smaller trifoliate leaves and purple flowers. If the flowers are not present, the best distinguishing feature is the leaf petiole which is angular on Hairy Cowpea and rounded on Eastern Milkpea.
The flower is primarily pollinated by a wide variety of native and exotic bees. To get to the nectar, the bee has to land on the two lower flower petals that function as a landing platform. When the bee lands on the two petals, the stigma and anthers are pushed up from underneath so that the pollen are stuck to the bee’s ventral abdomen and carried to the stigma of the next flower.
While the plant is rarely pollinated by butterflies, it is the larval host for the gray hairstreak (Strymon melinus), cassius blue (Leptotes cassius), and the long-tailed skipper (Urbanus proteus).