What Is a Hyacinth Bean?

Appearance

• The hyacinth bean is a fast-growing, twining vine that produces attractive pea flowers in shades of white and purple during early summer and early fall. The flowers grow on 6-inch peduncles or long stems that extend beyond the foliage and are followed by 2- to 3-inch-long, flat, slightly curved bean pods. Usually as showy as the flowers, the pods develop three months after planting and contain dark beans when cut open. The green or purple foliage of the twining vine grows 6 inches wide and long. The two varieties of the vine are Ruby Moon, with pink flowers and deep purple pods, and Alba, with light purple or white flowers.

Uses

• Originating from tropical Africa, the perennial vine is cultivated as a food crop in different parts of Asia. An excellent source of nitrogen, the bean is also grown for livestock fodder or as a ground cover. Unlike older pods that need to be de-stringed, immature pods are eaten like green beans. The hyacinth bean vine is grown as an ornamental plant in home and commercial gardens across the United States. The fast-growing vine spreads quickly to cover a trellis, arbor or fence, providing a natural screen. Its fragrant flowers attract butterflies and hummingbirds to the garden. Use the vine to conceal unappealing parts of your yard such as a chain like fence or compost pile.

Culture

• The hyacinth bean vine is a hot-weather plant that thrives in the South. It grows taller than 30 feet in frost-free areas, where it becomes woody. The vine remains herbaceous and does not grow longer than 10 feet in USDA Hardiness Zone 9. It thrives in well-draining soil exposed to full sunlight. Once established, the plant is moderately drought-tolerant and survives without water for two to three weeks.

Considerations

• Avoid eating the vine's dry seeds, which can cause vomiting and convulsions. Cook them in two changes of water to remove harmful effects. Pick beetles on the plant with tweezers, or use an insecticidal spray; don't eat the seeds if they have been exposed to insecticide. Because the plant grows fast, prune it frequently to keep its size in check.