Common Name: sweet potato
Type: Herbaceous perennial
Native Range: Indonesia
Zone: 9 to 11
Height: 0.50 to 1.00 feet
Spread: 8.00 to 10.00 feet
Bloom Time: Rarely flowers
Bloom Description: Pale pink to violet (cultivars mostly non-flowering)
Sun: Full sun
Suggested Use: Annual, Ground Cover
Tolerate: Deer, Drought, Dry Soil
Tender perennial that is winter hardy to USDA Zones 9-11. In St. Louis, grow as an annual or dig tubers in fall. Easily grown in average, medium, well-drained soils in full sun. Best leaf color usually occurs in full sun. Consistently moist soils are best. This is a tuberous plant that is not grown from seed. Purchase plants in spring and set out after last frost date. In fall before first frost, dig, dry and store tubers in a dry medium (vermiculite or peat) in a cool dry corner of the basement. When tubers sprout in spring, cut them into sections (at least one eye per section) and plant the sections outdoors after last frost date. Tubers can also be sunk ½ way into a large-mouthed glass jar of water in early spring to generate sprouts that can be removed and planted. Container plants and or rooted cuttings taken in late summer may be overwintered indoors in bright sunny locations. Best to rotate plantings to different locations of the garden from year to year to minimize possible fungal disease problems.
Ipomoea batatas, commonly called sweet potato or sweet potato vine, is native to tropical America. It is a tuberous rooted tender perennial that has been cultivated for its orange-fleshed edible tubers for over 2000 years. It was reportedly brought back to Europe from the New World by Columbus. Today, the sweet potato is a popular root vegetable that is grown in vegetable gardens and as a commercial food crop throughout the world. Although species plants and varieties grown as food crops have somewhat attractive green foliage, it is the more recently introduced purple-, chartreuse- and variegated-leaved cultivars that have transformed this vegetable into a popular ornamental foliage plant. If grown as a ground cover, plant stems typically mound to 9” tall but spread by trailing stems to 8-10’ wide, rooting in the ground at the nodes as they go. Leaves of the ornamental varieties are heart-shaped to palmately-lobed (to 6” long) and come in bright green, dark purple, chartreuse and variegated (green with pink or white) colors. Although species plants produce pale pink to violet trumpet-shaped flowers, ornamental varieties usually do not flower. Tubers of the ornamental varieties are edible, but are not as tasty as those of the varieties specifically bred for food production.
Genus name comes from the Greek words ips meaning worm and homoios meaning resembling, in probable reference to the sprawling underground roots of genus plants. On the other hand, some experts suggest the genus name is in reference to the worm-like twining plant habit.
No serious insect or disease problems. Fungal leaf diseases are somewhat common, particularly if plants are grown in the same garden area year after year. Watch for thrips and flea beetles.
Species cultivars are ornamental subtropical vines that are most often used as sprawling ground covers or as foliage contrasts grown to hang down over the edge of containers or window boxes.