I was at my daughter's house looking after her baby while she worked, and happened to spot on a high shelf (looking for something to make apple crumble in) a bowl FULL of sprouting sweet potatoes. Sprouts about three inches long! Forgot to take them home with me, but will ask her not to throw them away if she suddenly remembers them.
But it's the wrong time of year....do you think it will work if I put all the sprouts into jam jars to grow roots, then pot them up in a month until it is warm enough to plant them?