Incarvillea delavayi

Common Name: incarvillea 
Type: Herbaceous perennial
Family: Bignoniaceae
Native Range: Southwestern China
Zone: 5 to 7
Height: 1.50 to 2.00 feet
Spread: 1.50 to 2.00 feet
Bloom Time: July to August
Bloom Description: Pinkish-red with yellow throat
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Flower: Showy

Culture

Easily grown in average, medium, well-drained soil in full sun to part shade. Prefers deep, moist, sandy soils in full sun. Intolerant of the hot and humid summers of the deep South and needs some afternoon shade in southern locations. Remove faded flowers to prolong bloom period. May not be reliably winter hardy in the northern parts of USDA Zone 5. Mulch crowns with straw in cold winter locations. Carrot-like tap root makes division difficult.

Noteworthy Characteristics

Incarvillea delavayi, commonly called hardy gloxinia, is a clump-forming perennial which typically grows 18-24" tall. Features clusters of trumpet-shaped, pinkish-red, 2.5" long flowers with yellow throats (5-12 flowers per cluster). Clusters appear in summer atop sturdy, essentially leafless flower stalks which extend well above the basal, arching, fern-like, pinnately compound, medium green leaves (to 12" long).

Genus name honors Pierre d'Incarville (1706-1757), French missionary in China and botanical correspondent of the great botanist Bernard de Jussieu.

Problems

Slugs are frequent visitors.

Uses

Borders and rock gardens.