The purple hyacinth bean vine (Dolichos lablab) is a striking fast-growing annual climber that reaches a height of 20 feet during one season. Six-inch, heart-shaped leaves make a dense purplish-green screen. Purple or white fragrant flowers bloom in summer. Dark purple seedpods follow, and when dried, provide the seeds for next year's vine. This lush, tropical vine is easy to love and easy to grow.
Select a planting location. Hyacinth bean vines prefer a sunny location or one with light shade. Moist, well-drained soil is preferred, and give the vine plenty of support, such as a trellis, arbor or fence.
Prepare seeds for planting. Hyacinth bean seeds may be planted directly into the garden soil when there is no more danger of frost. Nick the seeds with a knife and soak the seeds overnight in water to improve germination.
Plant the seeds. Seeds should be planted 1 1/2 inches deep and seedlings should be thinned to 6 inches apart. Hyacinth bean germination takes approximately 2 to 3 weeks.
The hyacinth bean vine grows well in all hardiness zones during warm weather. In zones 10 and 11 the vine is considered a perennial. Container specimens may be difficult to find, but are sometimes found at nurseries. The vine does not transplant well. Plant them no deeper than their pot and space multiple vines a foot apart. Keep them watered well. The vine seeds may also be started in 3-inch peat pots and then planted outdoors. Place 2 or 3 seeds in a peat pot filled with a soilless potting mix, just barely covering the seeds. Moisten and keep in a warm, indoor location until germination. Use a pair of scissors to snip off weak seedlings and plant the vine and pot outdoors when danger of frost has passed.