For over 2,000 years, the tasty orange tubers of Ipomoea (Ipomoea batatas), more commonly known as sweet potatoes, have been cultivated as a food staple. This tender perennial vine grows in U.S. Department of Agriculture plant hardiness zones 9 through 11 depending on cultivar. Ornamental sweet potato cultivars, which can also be grown as annuals, cascade over containers, window boxes and hanging baskets, and intertwine among other plants in garden beds and along borders. They create eye-catching ground covers and can be trained to climb a trellis. The seeds of some ornamental cultivars are toxic, if ingested.
Showy green leaves edged in pink and white appear on “Tricolor,” also known as “Pink Frost.” “Blackie” sports dark burgundy leaves. Both vines trail up to 6 feet long. “Margarita” flaunts chartreuse leaves, the most popular foliage color, and reaches a length of 3 feet. All three varieties are fast growing and display heart-shaped to palmate-lobed leaves that grow to 6 inches across.
Edible Versus Ornamental
Soft pink to violet, trumpet-shaped blossoms burst into bloom on sweet potato plants, but the cultivars rarely flower. Although common sweet potato plants bear fairly attractive green leaves, the ornamental varieties brighten the landscape with multi-hued foliage. While both produce edible tubers, those grown specifically as a food source provide a wealth of flavor, whereas the taste of the tubers on the ornamental varieties is substandard.
Winter Tuber Storage
Before autumn’s first frost, sweet potato tubers can be dug up, dried and stored in peat or vermiculite, then set in a cool, dry area of the basement. When the tubers sprout in spring, cut them into sections, taking care to include a minimum of one eye per section. The sections should not be planted outside until after the last frost. Change the location of the plants each year, to avoid the possible occurrence of fungal diseases.
Indoors, a vine with a number of stems will sprout from a sweet potato that has been placed pointed side down in water inside of a container, with the top third of the potato exposed. To promote fuller growth, the vine can be cut back a few inches as it grows longer. Once transplanted into a container with potting soil, placed in a bright, sunny spot and fertilized monthly, it becomes a suitable houseplant similar to ivy. A sweet potato plant cultivated outdoors prefers a site exposed to full sun and consistently moist, well-drained soil but tolerates dry soil and drought. Sweet potato plants experience no serious disease or insect problems.
- Missouri Botanical Garden: Ipomoea Batatas
- University of Illinois Extension: The Homeowner's Column: Sweet Potatoes Move From the Plate to the Estate
- Sunset: Ipomoea Batatas
- Fine Gardening: Plant Guide: 'Pink Frost' Sweet Potato Vine
- Fine Gardening: Plant Guide: 'Margarita' Sweet Potato Vine
- Fine Gardening: Plant Guide: Sweet Potato Vine
- University of Illinois Extension: Grow a Sweet Potato Vine
- Floridata: Ipomoea Spp.