Coral Bean or Cherokee Bean. When I was a child our family spent many weeks during the summer and fall on Edisto Island, SC. Within just a hundred yards of the beach, our native Coral Bean grew on what is best described as sterile beach sand, but since it is a Legume, it could generate its own nitrogen and thrive on this otherwise impossible environment. One summer when I was about 8 years old, I spent most of my spare time digging up one of the "clumps." It ended up being a large woody "tuber" as large as a volley ball. I carried it home and planted it in my garden where it thrived for over 30 years until my mother sold the property. It makes 36" spikes of brilliant red flowers from late May to July and in the fall it produces bean pods with brilliant red seed (which are poisonous by the way). Its best flowers are in full sun where it makes a marvelous hummingbird and butterfly attractant. In south Florida where it is not killed to the ground by cold, it can reach upwards of 16'. In zone 7b it would be best to mulch for cold protection. This particular selection was found in the Santee State Park which sits between Columbia and Charleston, by some of the horticulturists from Moore Farms and Gardens, and it is the furthest inland that I have ever seen this species growing. So it may be a few more degrees hardier than others.