Native Plants

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Monday - May 21, 2012

From: Sylvania, OH
Region: Mid-Atlantic
Topic: Invasive Plants, Non-Natives, Poisonous Plants, Vines
Title: Non-native Purple Hyacinth from Sylvania OH
Answered by: Barbara Medford

QUESTION:

I am wondering if I plant a Purple Hyacinth Bean vine seed under a tree and allow it to grow up the tree trunk, will it kill the tree?

ANSWER:

Lablab purpureus (Purple Bean Hyacinth) is a tender perennial native to Africa. The Lady Bird Johnson Wildflower Center is dedicated to the growth, protection and propagation of plants native not only to North America but to the area in which those plants grow naturally.

So, while we have no information on this plant in our Native Plant Database, we can refer you to some websites that do. First, here is a very good rundown of the characteristics of the plant from the Missouri Botanical Garden.

Another description of characteristics of this plant from North Carolina State University includes the toxcity of the bean. This article from Dave's Garden indicates that it would be an annual in your USDA Hardiness Zone, as it is not winter hardy. Also, in terms of its invasiveness, you might want to read this comment in that same article:

"The plant is lovely and easy to grow. However, be careful where you plant it because it can become invasive. It will take over and shade out other plants. Also, it is a prolific seed producer. I planted one about 6 years ago and loved it the first year. However, I am still trying to get rid of its off-springs."