Introduction

This sprawling, evergreen shrub or small ornamental tree ranges from 10 to 15 feet (20 feet with proper training) in height. Older trees become much wider. It is the easiest tibouchina to train into a tree. It can be trimmed to any size and still put on a vivid flower display. The dark green, velvety, 4- to 6-inch-long leaves have several prominent longitudinal veins. Large, royal purple blossoms, flaring open to 2 inches, are held on terminal panicles above the foliage, creating a spectacular sight when in full bloom. Some flowers are open throughout the year but they are especially plentiful from May to January.

General Information

Scientific name: Tibouchina granulosa

Pronunciation: tib-oo-KYE-nuh gran-yoo-LOW-suh

Common name(s): purple glory tree

Family: Melastomataceae

Plant type: tree

USDA hardiness zones: 10B through 11 (Fig. 2)

Planting month for zone 10 and 11: year round

Origin: not native to North America

Uses: near a deck or patio; screen; specimen; container or above-ground planter; trained as a standard

Availability: generally available in many areas within its hardiness range

Description

Height: 15 to 20 feet

Spread: 15 to 20 feet

Plant habit: round; irregular outline or silhouette

Plant density: dense

Growth rate: moderate

Texture: coarse

Foliage

Leaf arrangement: opposite/subopposite

Leaf type: simple

Leaf margin: serrulate

Leaf shape: ovate

Leaf venation: parallel

Leaf type and persistence: evergreen

Leaf blade length: 4 to 8 inches

Leaf color: green

Fall color: no fall color change

Fall characteristic: not showy

Flower

Flower color: purple

Flower characteristic: spring flowering; summer flowering; fall flowering

Fruit

Fruit shape: round

Fruit length: less than .5 inch

Fruit cover: dry or hard

Fruit color: brown

Fruit characteristic: inconspicuous and not showy

Trunk and Branches

Trunk/bark/branches: not particularly showy; no thorns

Current year stem/twig color: green

Current year stem/twig thickness: medium

Culture

Light requirement: plant grows in full sun

Soil tolerances: clay; acidic; well-drained; sand; loam

Soil salt tolerances: unknown

Plant spacing: not applicable

Other

Roots: usually not a problem

Winter interest: no special winter interest

Outstanding plant: not particularly outstanding

Invasive potential: not known to be invasive

Pest resistance: long-term health usually not affected by pests

Use and Management

Purple glory tree is ideal for the mixed shrubbery border or can be used in small groupings to compound the impact of bloom time. Trees can become nicely shaped with some early pruning to provide for strong, upright trunks. The canopy will need to be pruned regularly to keep lower branches from drooping to the ground.

Full sun is best for flowering and the plant will thrive on any well-drained soil when regularly watered. Its growth habit is somewhat weedy, requiring training and pruning, especially when it is young, to develop and maintain it as a tree. It can be trained as a standard or espaliered against a south- or west-facing wall receiving at least 5 hours of full sun. It can also be trained on a trellis or arbor as a vine. Pinching new growth helps increase branching and will enhance the flower display on small plants.

Propagation is by cuttings.

Pests and Diseases

Scales and nematodes can limit growth.

Mushroom root rot can occur in soil that is kept too wet.