About the Vine
Sweet potatoes are not true vining plants like a pole bean and don’t twine. However, they will ramble and can be trained on a support. They can also be tied onto something like a chain link fence or trellis. The leaves grow in whorls of five each along the vining stems. Edible sweet potatoes can grow 16 feet or more. Semi-bush varieties are usually five or six feet and bush varieties three feet.
Ornamental Sweet Potato Vines
Plant breeders have tinkered with the original sweet potato varieties to produce purely ornamental varieties. These are usually bush or semi-bush and suitable for growing in containers. They are available in colors as widely different as a deep, purple-black, lime green and multicolored varieties. Most ornamentals don’t produce much in the way of tubers.
You have the choice of strictly ornamental, strictly edible or dual-purpose varieties. All require similar care. Among the possibilities:
- Beauregard – edible; common commercial variety.
- Blackie – ornamental; dark purple foliage.
- Centennial – edible; deep orange-red tubers.
- Illusion Emerald Lace – ornamental; light green, finely divided foliage.
- Sweet Caroline – ornamental; copper-bronze foliage.
Growing Sweet Potatoes
Both ornamental and edible sweet potato vines are grown in the same way. Sprouts, called slips, are started from a sweet potato tuber and planted once they have developed some roots. They should be spaced about 18 inches apart in loose, friable soil of moderate fertility that is slightly acid. Both kinds of vines do better with regular water.
Managing the Vines
How much you need to manage the vines depends on how big the plant gets and how much space you have. A small, container-grown ornamental bush variety may not need trimming. A semi-bush variety might do better tied to a trellis if you have limited space. Even if you have a lot of room, you may want to guide full-size vines so they grow where you want them to.
Harvesting Sweet Potato Vines
Sweet potato vines are edible, whether they are the regular plants or ornamental varieties, and so are the tubers of both types. You can harvest leaves of any size, but young leaves will be more tender. Leaves of ornamental varieties are more likely to be bitter, as the plants are bred for qualities other than taste. Tubers of ornamental varieties are also more likely to be very starchy and less sweet.