Common Name: twinspur
Type: Herbaceous perennial
Family: Scrophulariaceae
Native Range: Temperate southern Africa
Zone: 8 to 11
Height: 0.75 to 1.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: April to frost
Bloom Description: Pink with yellow throat
Sun: Full sun
Water: Medium
Maintenance: Medium
Suggested Use: Annual
Flower: Showy
Culture
Tender perennial that is winter hardy to USDA Zones 8-11. In St. Louis, it is typically grown as an annual. It is best grown in moderately fertile, organically rich, consistently moist, well-drained soils in full sun. Seed may be sown directly in the garden 1-2 weeks before last frost date or started indoors 6-8 weeks earlier. Pinch stems of young plants to promote bushiness. Deadhead spent flowers to prolong bloom. Plants sometime struggle in hot summer climates such as St. Louis, and may temporarily stop blooming in the heat of the summer. When flowering declines, shear planting to promote a fall bloom.
Noteworthy Characteristics
Diascia barberae, commonly called twinspur, is a mat-forming plant that typically grows to 12” tall and spreads to 18” wide. Features loose terminal racemes of pink flowers (3/4” across) with yellow throat spots and two downward-angled spurs. Flowers appear above the foliage from summer into fall on stems rising 6-12” tall. Ovate toothed glossy green leaves (to 1” long).
Genus name comes from the Greek words di meaning two and kaskos meaning sac or pouch in reference to the two spurs.
Problems
No serious insect or disease problems. Watch for snails and slugs.
Uses
Borders, rock gardens, pots/containers, hanging baskets.