My SIL, Carol, who started this thread, gave me one slip from her Sand Hill order. I just wanted to grow one because I thought it might be fun for the kids. Anyway, I chose Ivis White Cream from her assortment and planted it and then forgot about it all summer. I mulched it with some straw and watered it now and then but that's it. Yesterday I dug up three ENORMOUS sweet potatoes. They're huge! I think each one could feed four people! I guess I should have dug them up a month or so ago but I didn't know any better. Next year I'll place my own order and grow more. I was really pleasantly surprised with my one vine.