"The Jerusalem artichoke (Helianthus tuberosus L.), also called the sunroot or sunchoke or topinambur, is a flowering plant native to North America grown throughout the temperate world for its tuber, which is used as a root vegetable."
The above photo is my mother's crop of "topinambur" which grows near her driveway. They are replants from my yard--her mother's yard. A Cajun delight, the tuber/root is cooked in stews and gravies, and pickled. When plants finish flowering, the stalks dry up. Then the tubers can be dug up, cleaned and prepared.
Pretty flowers-- But the real treat is beneath the ground.