DEAR IRIS Hyacinth bean vine gets ‘wow’

By Gerri Lyon, Master Gardener intern | Sep 13, 2012

PHOTO SUBMITTED The hyacinth bean vine, a really fast grower, has large, heart-shaped deep-green leaves and sickle-shaped, burgundy colored bean pods.

While spending the day in the Amanas with a friend last fall, I made a great discovery. At the entry area to a shop, grew a thick, heavily foliaged vine with lovely, purple flowers that looked similar to pea blossoms. But what really caught my eye were stems of glossy, burgundy curved pods. It was labeled, Hyacinth Bean Vine. This interesting specimen was added to my “imagine” list for this years’ garden areas. As I looked for seeds, most catalogs said there was a limited supply. Fortunately, my order arrived!
The lablab purpureus is a fast, really fast grower. I started the seeds in pots, and transplanted them to the ground in three different locations. The earliest bloomers are in full sun, the nicest foliaged plants are receiving six hours of sun. I had concerns in mid-August about flowering, but finally buds appeared and all the plantings are in full bloom at last! Many seedpods are setting on. I will let them fully mature and dry for sharing and planting in 2013.
Hyacinth beans are used as a common food source in Africa and Asia. My research tells me that the beans are poisonous when mishandled. The beans should be boiled two times with a water change to be safely eaten. The flowers can be eaten, also. Honestly, I appreciate them as an ornamental, attractive vine in the gardens with no edible purpose intended. They are a wholesome food source for hummingbirds and butterflies. Hummingbirds are bypassing the syrup feeders to fill up at the hyacinth bean vines! Almost nonstop feeding occurs for the birds, but I haven’t seen many butterflies.
In the Discovery Gardens Pergola at the Iowa State Fair, the Master Gardeners planted this vine. It had covered the pergola entirely with its really fast growth and was just showing buds. Many admirers had gathered with questions on blooming time.
I watered all of the vines because of the intense heat and drought. I used liquid Miracle Gro when I fertilized. Be sure to give the vines a strong place to grow like a woven wire fence, large trellis that is secured, pergola, etc. It will grow 10 to 15 feet high if given the space! If pods are allowed to mature and remain on the vine after frost, I feel confident that volunteer plants will grow next spring. I won’t disturb that area by hoeing or tilling to allow growth.
The bean stems with pods are a popular addition to fresh flower arrangements. The burgundy color adds a punch while the sickle shape of the pods adds the unusual touch. The color is delightful in fall bouquets.
This vine has been a wonderful addition to each planted area. Blooming started at a time when I needed the color! It has large, heart shaped leaves that are a deep green. Did I mention how fast it grows? Hyacinth bean vine is a great performer that gets a WOW response from visitors!