Ask the Expert: Purple Flowering Vine
We live in central Oklahoma. It is now mid September and my neighbor brought me these purple flowers off a vine he found growing up his cucumber trellis.

He has lived in his home for 29 years and did not plant this flower.  The vine is purplish in color and the blossoms are shapped similar to a butterfly.  I hope the pictures show you enough detail for identification. Sandy

Plant Expert Reply:

It looks like a hyacinth bean vine (Dolichos lablab) bloom.  You should start to see purple bean pods.  This vine with heart-shaped leaves is considered a short-lived perennial in frost-free areas.  Most people grow it as an annual.

Although the beans can be cooked and eaten, they are poisonous when eaten raw. Birds probably dropped the seeds in your neighbors garden.