Tibouchina urvilleana
Common Name: princess flower 
Type: Broadleaf evergreen
Family: Melastomataceae
Native Range: South America
Zone: 9 to 11
Height: 6.00 to 8.00 feet
Spread: 6.00 to 8.00 feet
Bloom Time: Seasonal bloomer
Bloom Description: Rose purple
Sun: Full sun
Water: Medium to wet
Maintenance: Low
Suggested Use: Naturalize
Flower: Showy
Leaf: Evergreen
Other: Winter Interest
Tolerate: Wet Soil

Culture

Winter hardy to USDA Zones 9-11. In Zones 8, plants will typically die to the ground in winter, but will often grow back from the roots in spring. This shrub is best grown in moist, acidic, organically rich, fertile, well-drained soils in full sun. Prefers some afternoon shade in hot summer climates. Shelter plants from strong winds. Apply mulch to keep roots cool. Plants will spread in garden areas by suckers. Lightly prune plants after flowering to control unwanted legginess and spread. In St. Louis, this shrub may be grown in containers which are typically sunk to the rim in garden areas or placed on patios or decks throughout the growing season. Plants are sensitive to frost, however, and containers should be brought indoors to a cool bright room for overwintering as houseplants before first fall frost.

Noteworthy Characteristics

Tibouchina urvilleana, commonly called princess flower or glory bush, is a large, dense, rounded-but-sprawling, tropical shrub that typically grows to 6-8' tall, but may reach 15' in optimum growing conditions. It can be trained as a small tree. It can also be trained as a vine for growing on an arbor or trellis. It is native to rainforests of Brazil. It thrives in southern Florida and along the California coast. It is now considered to be a noxious weed in Hawaii where it has escaped gardens and naturalized. Reddish, pubescent, somewhat brittle, square branches are clad with serrulate, downy, ovate to ovate-oblong (2-4" long) evergreen leaves, each having 3-7 prominent longitudinal veins. Rose-purple flowers (to 3-4" diameter) with purple stamens bloom singly or in clusters in summer. In tropical areas, it will bloom sporadically throughout the year. Full bloom is often spectacular. Fruit is a 5-valved capsule.

Genus name comes from the native name in Guiana.

Specific epithet honors Jules Sebastien Cesar Dumont d'Urville (1790-1842), French explorer and botanist.

Problems

Scale and mealybugs may appear. Watch for spider mites on indoor plants. Overly moist, water-logged soils can lead to root rot.

Uses

Where winter hardy, this is an outstanding flowering shrub for garden areas. Accent or small groups. Can be trained as a vine. Container plants may be brought indoors for overwintering in areas where plants are not winter hardy.