Begoniaceae Agardh 1824
The Begoniaceae is a family of 2 genera and around 1400 species of tropical flowering perennials, mainly from America and Asia, with a few African species. The monotypic genus Hillebrandia Oliver (1866) is native to the Hawaiian islands. All other species are included in Begonia which also lends its name to the Family Begoniaceae.
The genus Symbegonia Warburg (1905), a group of 12 species from New Guinea with distinctive tubular female flowers, was recently merged into Begonia.
Begonia Linnaeus 1753
Named for Michel Bégon, former French colonial governor of Haiti.
Begonias are typical understory plants in humid, tropical forests and cloud forests and rarely xerophytic. Most species are evergreen with fibrous roots. Some are tuberous with deciduous foliage. Stems are generally succulent with broad, asymmetrically shaped brittle peltate leaves, sometimes furnished with hairs especially on the undersides. Leaves of some cultivars may have decorative zonal markings. Flowers are unisexual with 2 - 5 prominant sepals, separate or absent petals, 4 to many stamens and 2 - 5 carpels. In some species the male flowers are smaller and much less showy than the female flowers.
Begonias are cultivated for decorative effect, popular as free-flowering houseplants and for summer bedding. They grow well in any general free-draining potting compost and require regular watering. Root and stem rot occur easily if the compost remains excessively wet for prolonged periods. Sudden changes in growing conditions may cause flower buds and leaves to drop.
Most species can be readily propagated by stem cuttings. Begonia rex is noteworthy as it will form plantlets from leaves laid on the surface of the soil and cut across their width.