Someone wrote about making your own slips from putting sweet potatoes halfway in water. It worked great, I have thin white roots growing in the water. I also have very thick purple ones on top of the dry part of the potato. I'm supposed to pull them off and plant them after the last frost. What I'm wanting to know is, is it the thick top part or the thin roots in water that gets pulled off. The thin ones don't seem sturdy enough to live after replanting. Any help would be appreciated.