I got five good long sprouts off of two potatoes - the other four just mainly have long roots on the bottoms and tiny sprouts. hopefully they all catch up. this one sweet potato grew sooo fast this week. almost every time I passed by it the leaves were a little bigger and taller. it was pretty cool to watch! :) I have no idea why this one did so well.
they all had tiny little fingers coming off the ends of the stems when I pulled them off the potato. I'm assuming that's what turns into the roots now?