Solanum citrullifolium is a species of flowering plant in the Solanaceae family.[2] It is a nightshade referred to by the common name watermelon nightshade,[3] as its leaves somewhat resemble those of a watermelon plant (the melon-leaved nightshade is a different species, S. heterodoxum, whose leaves resemble those of a normal melon plant). It is a white-stemmed shrub with purple star-shaped flowers. It is native to the southern United States and it is grown in home gardens as an ornamental plant.