Sweet potato, known as sweet potato, is a leguminous herb vine. Thick, twining, slightly hairy, sometimes slightly woody at the base.

The raceme is 15-30 cm long, with 3-5 flowers per section; Bracteoles setose, caducous; Calyx is 9- 1 1 mm long and densely covered with long bristles; Corolla light purple or reddish, flag nearly round; 8- 10 capsules per pod, nearly square; Root block, spindle-shaped or oblate, generally about 20-30 cm in diameter, fleshy.

Extended data

Cold potato likes high temperature, and the temperature required for seed germination is higher than that of general leguminous crops. Plants need sufficient light for vigorous photosynthesis and accumulated assimilation and nourishment, especially during the formation of fleshy roots. Only sufficient light can produce high yield. The requirement of cold potato for soil is medium fertility and sandy loam.

If planted in cohesive soil, the root tuber will be stunted, with rough skin and more fibers. In sandy loam, the root tuber is big and the meat is tender. If the soil is too fertile, it will often cause the vines to grow white, but the fleshy roots will not grow.

Sweet potato itself tastes sweet and juicy, suitable for eating in hot summer, which can not only relieve summer heat, but also clear away liver fire and reduce dryness and heat. Sweet potato is generally regarded as fruit, peeled and washed and eaten raw. Raw sweet potatoes are crisp, sweet and full of water. As a vegetable, it can be said that the sweet potato is shredded and mixed with cold dishes such as rice vinegar, sugar and sesame oil, which is not only sweet and sour, but also appetizing, clearing heart and quenching thirst.