Hibiscus grandiflorus Giant Rose Mallow The five pink petals of swamp rose-mallow flowers each have a red to purple center, are 4-6 in. long, and surround many stamens. Flowers nod slightly from leaf axils and occur singly. Velvety, alternate leaves are heart-shaped, three-lobed, and toothed. Seed pods are also velvety. This shrub-like, herbaceous to somewhat woody plant grows to 6 ft. tall or more.

Swamp Hibiscus is a member of the mallow family (family Malvaceae) which includes herbs, shrubs, and rarely small trees, often velvety with starlike or branched hairs, the flowers borne singly or in branched clusters. There are about 85 genera and 1,500 species, many in tropical America. Rose-of-Sharon and other Hibiscus, and Hollyhocks are grown as ornamentals. Okra is the edible fruit of one species of Hibiscus, and the hairs of seeds of Gossypium provide the fiber cotton.