I just removed a sweet potato vine from a planter and noticed that there are many small tubers underneath. Can one hold these tubers over the winter and start new plants in the spring?
According to Janet Bohac at the USDA’s Vegetable Laboratory (and others), it is indeed possible to grow the vines from the tubers, but propagation from cuttings is the much easier and preferred method.
If you decide to overwinter the bulbs, when you pot them up in the spring do not cover the entire root with soil. The tubers like to be kept quite warm, in sandy, well drained soil. You could also start them in water. Stick a few toothpicks around the middle of the tuber. Rest the toothpicks on the edge of a glass with water that covers half of the tuber. Place it in the dark for 1-2 weeks and then on a sunny windowsill.
As the vine grows, you could take cuttings. Not only will they root easily, you will make the mother plant bushier. You could then plant it in well drained soil, again not entirely covering the tuber. Of course, many people grow sweet potato vine as a houseplant, so you could really start them anytime and enjoy them all year round