Sweet potato is panicum miliaceum, and its underground part has round, oval or spindle-shaped tuberous roots. The shape, skin color and flesh color of tuberous roots vary with varieties or soils. Stems procumbent or ascending, occasionally twining, multi-branched, cylindrical or angular, green or purple, sparsely pilose or hairless, and stems are prone to adventitious roots. The shape and color of leaves are often different for different varieties, and sometimes there are different leaf shapes on the same plant. Generally, it is broadly ovoid, 4 ~ 13cm long and 3 ~ 13cm wide, with 3 ~ 5 (~ 7) lobes, broadly ovoid, triangular ovoid or linear lanceolate, with heart-shaped or nearly truncated leaves at the base and tapering at the top. Petioles vary in length, 2.5 ~ 20 cm long, sparse or glabrous. Cymes axillary, 1 ~ 3 ~ 7 flowers cymose, peduncle 2 ~ 10.5 cm long, slightly stout, hairless or sometimes puberulent; Bracts are small, lanceolate, 2 ~ 4 mm long, with awn tips or acute tips at the top, caducous; Pedicel length 2 ~ 10 mm; Sepals are oblong or oval, with different lengths. The outer sepals are 7 ~ 10 mm long, and the inner sepals are 8 ~ 1 1 mm long. The top suddenly becomes awn-pointed, with no hair or sparse cilia. Corolla pink, white, lavender or purple, bell-shaped or funnel-shaped, 3 ~ 4 cm long, glabrous outside; Stamens and styles are embedded, and filaments are hairy at the base; Ovary 2-4-loculed, hairy or sometimes glabrous.