Coca is any of the four cultivated plants in the family Erythroxylaceae, native to western South America.The plant is grown as a cash crop in Argentina, Bolivia, Colombia, Ecuador, and Peru, even in areas where its cultivation is unlawful.It also plays a role in many traditional Andean cultures as well as the Sierra Nevada de Santa Marta (see Traditional uses). Coca is known throughout the world for its psychoactive alkaloid, cocaine.