Mexico
Creeping vine with milky sap, glabrous or pubescent, with enlarged tuberous edible roots; leaves ovate-orbicular, entire or palmately 3-7-lobed or -parted, cordate or subcordate, 4-15 cm long, 3-11 cm wide, on petioles commonly 3-15 cm long; flowers several to many in long-peduncled cymes; calyx-lobes briefly mucronate, about 10-15 mm long; corolla usually pale rose-violet, rarely albino, 3-5 cm long; darker (purplish) in the throat; ovary mostly pubescent; fruit a capsule.
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.