Question: We call it an Air Potato but would like to know the formal name. Rapid growing, heart or spade shaped leaf 6" or better across. No flowers. Grows 'potatoes' on the vine (not underground). These 'potatoes' are round and can be up to 3" in diameter. It is not an Ipomoea batatus - not a sweet potatoe at all. In fact, if eaten, it's bitter. The original tuber in our circle of gardeners was reported to have come from Africa by way of London.
Answer: Air Potato is Dioscorea bulbifera, a member of the yam family. There are 9 or 10 genera, but only Dioscorea is cultivated, primarily in the tropics for its edible tubers.
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