1059 Thunbergia alataCommon Names: black-eyed susan vine Family: Acanthaceae (acanthus Family)
The black-eyed Susan vine is a perennial evergreen vine that climbs by twining. The opposite leaves are triangular with toothed margins, and average about 3 in (8 cm) long. The petioles (leaf stems) are winged ("alata" means wing). Throughout the summer, black-eyed Susan vine bears numerous bright yellow or orange flowers with (usually) purple-brown centers. The flowers have an elongate, tubular corrola about 2 in (5 cm) long that opens to five petal-like lobes, about 1.5 in (4 cm) across. The vines may be covered with flowers.
Black-eyed Susan vine is a rather delicate and slender-stemmed vine that can twist and twine for little more than 8 ft (2.4 m) or so. Several cultivars are available, including 'Alba' which has white flowers with purple-brown centers; 'Bakeri' with white flowers and white centers; and the various Suzie Hybrids which have dark centers and corrolas of orange, yellow or white.
Thunbergia alata is native to tropical East Africa.
CultureLight: Grow black-eyed Susan vine where it can get mostly full sun in the mornings and partial shade at midday. Moisture: Does best in a moist but well drained soil. It does not suffer drought well. Hardiness: USDA Zones 8 - 11. Black-eyed Susan vine is an evergreen perennial in Zones 10 and 11. In Zones 8 and 9, you can expect her to die to the ground in winter, but to return the following spring. Not only that, she can be planted from seed and grown as a frost-tender annual in even cooler climes, as long as there is at least five months of frostfree weather. Propagation: By seed.
Black-eyed Susan vine is an excellent evergreen vine for an arbor or arch (or even a tree) in tropical and subtropical gardens. She is sometimes used as a very showy ground cover. Black-eyed Susan vine is a tropical perennial, but she blooms in her first year from seed and therefore can be grown as an annual in climates less friendly to tropicals. Many gardeners grow this twining beauty in containers with on-board trellis support, or next to something it can climb up on. Although she is often pruned back hard once a year in the tropics, it is a shame to have to clip this beauty throughout the growing season, so be sure to give her something nice and big to climb on. Alternatively, let black-eyed Susan vine cascade from a hanging basket.
Don't confuse black-eyed Susan vine with black-eyed Susan (Rudbeckia hirta), which is an herbaceous annual (or sometimes perennial) in the daisy family (Asteraceae). Skyflower (Thunbergia grandiflora) however, is closely related, and is also a beautiful flowering vine that deserves to be planted in more gardens.
Steve Christman 9/22/07; updated 6/17/12