It is a unique colored sweet potato that is reddish purple inside, and the most consumed potato in Okinawa. The purple color contains polyphenol which has antioxidant effect, used for cooking, sweets such as cake and ice cream, cosmetic, and other various uses.I have started Japanese Sweet Potatoes in seven half-whiskey barrel containers. I got just as much yield from the container as I did from a Raised Bed, but it was so much easier to harvest the Okinawan Sweet Potatoes in the container. It would take me a over an hour to dig up the Raised Bed and find all of the Japanese Sweet Potatoes.