Last weekend I used 3 tiny sweet potatoes that were too small to eat to start my sweet potato slips. As you can see I'm using toothpicks to hold them above the glass rim that is filled with water. Only few days in and plenty of roots are already formed and first leaves starting to form.
Hopefully it will give me several more slips so I can have at least dozen plants. We really don't need more than that for our use.