I am trying to grow sweet potatoes this year. Research has told me that I needed to grow slips from a Sweet Potato and then root and transplant them into the soil in spring. I have been doing this and they seem to be coming along. Have a bunch of roots on the bottom and slips growing out of the top. However, something that is concerning me is that the potato is going soft in the middle and seems to be rotting. Anyone know if this is normal?