Lablab purpureus
Common Name: hyacinth bean
Type: Herbaceous perennial
Family: Fabaceae
Native Range: Tropical Africa
Zone: 10 to 11
Height: 10.00 to 20.00 feet
Spread: 3.00 to 6.00 feet
Bloom Time: June to frost
Bloom Description: Rose-purple, white, pink
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Annual, Vegetable
Flower: Showy, Fragrant
Leaf: Colorful
Attracts: Hummingbirds
Fruit: Showy, Edible
Tolerate: Drought, Dry Soil

Culture

Tender perennial that is winter hardy to USDA Zones 10-11 where it may be left in the ground year-round. In St. Louis, it is grown as an annual vine. It is easily grown in average, medium, well-drained soils in full sun. Plant seed directly in the garden after last frost date or start seeds indoors 6-8 weeks earlier. Needs a sturdy support structure on which to grow due to the weight of the vine at maturity. Collect seed in fall for planting the following year.

Noteworthy Characteristics

Hyacinth bean is an ornamental twining vine with handsome, purple-tinged, trifoliate leaves. It rapidly grows to 20' and will easily cover a trellis in a single season. Spikes of fragrant pea-like bright rose-purple flowers (sometimes white or pink) are followed in late summer by flat, glossy, ruby-purple seed pods (to 6” long). Young immature pods can be cooked and eaten. These plants are widely grown in northern Africa and parts of Asia as a vegetable crop for the flowers, leaves, immature seeds and edible pods. Mature, dried seeds are toxic due to high levels of cyanogenic glucosides and should be boiled in two changes of water before eating to remove the toxins. Given a sunny location, it will bloom continuously throughout the summer.

Problems

No serious insect or disease problems though it is much beloved by Japanese beetles, which can make the leaves resemble Swiss cheese. Vines survive, however, and produce handsome new foliage for late season enjoyment.

Garden Uses

Annual vine for covering walls, trellises or fences. Good annual privacy vine for porches. Effective ground cover. Containers. Vegetable gardens.