Q: I vaguely remember starting sweet-potato rooting. It seems that we took a sweet potato and suspended it in a small amount of water with toothpicks holding the potato. Are there more steps to starting roots?
--Karol Frechette, Preston, CT
Sweet-potato roots can indeed be started in water alone. However, this method will only produce a vine, and not the strong roots necessary for growing potatoes. If you want to grow sweet potatoes as a crop, you'll need to start them in soil.
Sweet potatoes are in the same family as morning glories and are easy to grow in the garden as long as they have plenty of summer heat and room to spread out. In northern climates, where the summer season is short, choose varieties like 'Beauregard' and 'Georgia Jet,' which take only about ninety days to mature, as opposed to the four months required by other types.
Start sweet potatoes from rooted "slips" in your garden. Slips are the shoots that grow out of dormant buds, or eyes, on potatoes that have been stored from the previous season and covered with mulch. Once the slips are detached from the parent tuber, they are ready to be planted. For a home garden, you can purchase rooted slips; they're generally inexpensive -- only about $15 for roughly fifty plants -- and this option allows you to try out the best-tasting varieties.
Check with your local garden center or mail-order supplier for specific planting instructions, as well as for the proper planting and harvesting times for your climate.