You are buying 10+ seeds of the Purple Hyacinth Bean vine (Lablab purpureus, Dolichos lablab). These are annuals.
I've grown these for several years now and I still say WOW every time I see them! To start with, the seeds/beans look like little 'Oreo" cookies that have had the filling squished out one side (my husband still calls them the 'Oreo Vine')! As they grow you get lovely, hunter green, heart-shaped leaves with purple veins followed by tall flower spikes with flowers that turn from a pink to a lovely purple color as they age - then the PIECE DE RESISTANCE: the large, deep purple seed pods! These seed pods really stand out against the lovely green foliage and are every bit as attractive as the flowers!
Hyacinth beans are fun to grow, They are self-sowing annuals they prefer full sun but can grown in partial shade and I've found them to be fairly drought tolerant once established. They sprout easily and grow quickly reaching 20 feet or more - a very vigorous vine and bloomer - blooming all summer to frost. It's been cultivated as a novelty plant in the U.S. for generations -- grown by Thomas Jefferson at Montecello!
If you're looking for a vine to cover a fence for privacy, THIS IS IT! These are fast growing, easy to maintain and attractive all summer into fall. Grow these on your fence, arbor or even as a ground cover - a perfect heirloom vine for your cottage garden! Oh, and don't forget the butterflies, bees, hummingbird moths and hummingbirds that frequent the flowers - they'll love them, too!
Information on edibility of this plant: https://www.eattheweeds.com/hyacinth-bean-purple-protein-and-more-2/
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