In all the years of growing them outdoors, I've never got a potato in the pot. What do you do with the potato? Can you save it to start more for next year or just get rid of it?
Sweet Potato Vines
Certified GKH Gardening Expert
Technically the tubers are edible, though the varieties for ornamentals are not very tasty. Also there may have been many chemicals used on these ornamental plants that are not considered safe for edibles. For this reason I would not advise eating the 'potatoes'.
If you would like to try to store the tuber, the link below will have storing information.