Tibouchina is a genus of flowering plants in the family Melastomataceae, native to the Neotropics from Mexico through tropical South America, reaching its greatest diversity in Brazil. The genus comprises evergreen shrubs, subshrubs, and small trees prized in cultivation for their velvety leaves and large, vivid purple to violet flowers with distinctive curved stamens — qualities that earned them common names such as "glory bush" and "princess flower." Following molecular phylogenetic studies, Tibouchina was substantially recircumscribed, with many former members transferred to genera including Pleroma and Chaetogastra.
Etymology
The genus name Tibouchina was established by the French botanist Jean Baptiste Christophe Fusée Aublet in 1775, based on a vernacular name for the plant used by indigenous people of the Guianas. The common names "glory bush," "princess flower," and "lasiandra" refer to the genus's spectacular purple flowering.
Distribution
Tibouchina is native to the Neotropics, ranging from Mexico and the Caribbean through tropical Central and South America. The genus reaches its greatest diversity in Brazil, where the majority of species occur, particularly in the Atlantic Forest and cerrado biomes.
Ecology
Species of Tibouchina are evergreen shrubs, subshrubs, and small trees. The flowers, typically purple to violet with prominent curved stamens, are adapted for buzz pollination by bees, which vibrate the anthers to release pollen. The genus is a characteristic component of Brazilian forest and savanna ecosystems.
Cultivation
Tibouchina are widely grown as ornamentals for their large, showy flowers and velvety foliage. They thrive in acidic, well-drained soil with full sun to partial shade. The plants are frost-tender, requiring a minimum temperature of around 7–10°C; in temperate climates they are grown in conservatories or as container plants that can be moved indoors. Tibouchina urvilleana is the most commonly cultivated species.
Propagation
Tibouchina is propagated from softwood cuttings taken in spring or semi-ripe cuttings taken in summer.
Taxonomy Notes
The circumscription of Tibouchina has changed substantially in the 21st century. Molecular phylogenetic studies (Guimarães et al.; Michelangeli et al.) showed the traditional broad genus to be polyphyletic, leading to the transfer of many species to other genera, including Pleroma, Chaetogastra, and Andesanthus. As a result, the modern genus is more narrowly defined than in older horticultural literature, where names such as T. urvilleana and T. semidecandra remain in wide use.
