They are thorny, woody vines growing anywhere from 1-12 meters tall, scrambling over other plants with their hooked thorns. The thorns are tipped with a black, waxy substance. They are evergreen where rainfall occurs all year, or deciduous if there is a dry season. The leaves are alternate, simple ovate-acuminate, 4-13 cm long and 2-6 cm broad. The actual flower of the plant is small and generally white, but each cluster of three flowers is surrounded by three or six bracts with the bright colors associated with the plant, including pink, magenta, purple, red, orange, white, or yellow. Bougainvillea glabra is sometimes referred to as "paper flower" because the bracts are thin and papery. The fruit is a narrow five-lobed achene.
