Mostly , colorful bracts (modified form of leaves) of Bougainvillea plant are believed as flowers, but between those bracts rest actual tiny flowers.
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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 that is easily left in the flesh of an unsuspecting victim. 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.
Bougainvillea are relatively pest-free plants, but may suffer from worms and aphids. The larvae of some Lepidoptera species also use them as food plants, for example the Giant Leopard Moth.