Black-eyed Susan vine Thunbergia alata Photo/Illustration: Michael Dirr 1 2 3 4 5 6 7 8 9 10 11 Black-eyed Susan vine (Thunbergia alata) Genus: Thunbergia This tender perennial climber is evergreen in Zones 10 and warmer. Cheerful, 1.5-inch flowers in shades of orange and yellow cover this fast-growing vine. The blossoms have a simple form: 5 petals surrounding a brownish purple center. Where grown as an annual, plants can reach 8 feet; when grown as a perennial, 20 feet. Noteworthy Characteristics: Annuals, perennials, and shrubs of this genus are native to warm or tropical regions of Africa, Madagascar, and Asia. Their showy, five-lobed flowers have slender tubes that open to form flat or undulating trumpets. In warmer climates, grow perennial climbers along permanent structures and shrubs in mixed borders. Some cultivars with whitish flowers are available. Care: Provide moist, well-drained soil in full sun with some afternoon shade. In cooler zones, grow in a warm or temperate greenhouse or treat as annuals. Propagation: Sow seed over 60°F, or start indoors 6-8 weeks before last frost date with heat. Problems: Whiteflies, scale, spider mites on indoor plants. Overview Height 6 ft. to 10 ft. Spread 6 ft. to 10 ft. Growth Habit Clumps Growth Pace Fast Grower Light Full Sun to Part Shade Moisture Medium Moisture Maintenance Moderate Characteristics Self Seeds, Showy Flowers Bloom Time Early Fall, Early Summer, Fall, Late Summer, Summer Flower Color Salmon, White, Yellow Uses Beds and Borders, Container, Specimen Plant/Focal Point, Trellis, Suitable as Annual Style Cottage Garden, Herb Garden Seasonal Interest Summer Interest Type Vines Related Plants to Thunbergia alata 1 2 3 4 5 6 7 8 9 10 11 Sweet autumn clematis Clematis terniflora 1 2 3 4 5 6 7 8 9 10 11 Clematis viticella 'Alba Luxurians' 1 2 3 4 5 6 7 8 9 10 11 Egyptian bean Lablab purpureus 1 2 3 4 5 6 7 8 9 10 11 Bitter melon Momordica charantia View the discussion thread.