Thunbergia grandiflora is a flowering vine native to India. This fast-growing vine can cover a section of a fence in one season. The beautiful flowers of the Thunbergia grandiflora occur in shades of blue, lavender and white, and appear from early summer until late in winter. The Thunbergia grandiflora is hardy in climate zones 9B through 11. Because of its spreading size, the Thunbergia grandiflora is usually planted in the ground, but it can be maintained as a container-grown specimen, as well.
Select a location to plant the seeds. The area should receive full sun, and the planting site should be near a sturdy fence or trellis so that the Thunbergia grandiflora has something to climb as it grows.
Plant Thunbergia grandiflora seeds in early spring after any danger of frost is past. Sow the seeds on rich, moist, well-drained soil and then cover them with a light layer of planting soil.
Water the soil regularly to keep it moist. Sprouts should be seen in about two to three weeks. Remove all but the strongest sprouts.
Fertilise sparingly, if at all. Thunbergia grandiflora needs fertiliser only in the poorest of soils.
Pull the vine ends of the young plant through openings in the fence or trellis. This trains it to climb. Once it has begun growing on the support, it will not need any additional help to continue climbing and spreading.
Prune the Thunbergia grandiflora to keep it contained, or it may spread beyond the chosen area. It can be cut anywhere along the branches or stems.
Cut off old flowers to promote extending flowering periods.
If subjected to light freezing conditions, Thunbergia grandiflora will die back to the ground. Cut off all of the exposed plant, to the ground, and it will resprout in the spring. If subjected to hard freezes, the plant may not survive.