potato or white potato, common name for a perennial plant ( Solanum tuberosum ) of the family Solanaceae (nightshade family) and for its swollen underground stem, a tuber, which is one of the most widely used vegetables in Western temperate climates. Evidence of the domesticated potato, which is native to South America, has been found at a 12,500 year-old archaeological site in Chile. The potato was cultivated by the Incas in the Andes, and in pre-Columbian times its culture spread widely among Native Americans, for whom it was a staple food.
Its history is difficult to trace, partly because the name potato was also used by early writers for the sweet potato ( Ipomoea batatas ) and for other unrelated plants. Spanish explorers are believed to have brought it in the 16th cent. from Peru to Spain, whence it spread N and W throughout Europe. It was brought to North America by European settlers probably c.1600; thus, like the closely related tomato, it is a reintroduced food plant in the New World. The potato was first accepted as a large-scale crop in the British Isles. It became the major food in Ireland during the 18th cent. and is hence often called Irish potato to distinguish it from the sweet potato. Ireland was so dependent on the potato that the failure (resulting from blight) of the 1845–46 crop caused a famine resulting in widespread disease, death, and emigration. The potato was also important to the course of history in the 20th cent. in Europe, especially in Germany, where it kept the country alive during two world wars.
The potato is today a primary food of Western peoples, as well as a source of starch, flour, alcohol, dextrin, and fodder (chiefly in Europe, where more is used for this purpose than for human consumption). Nutritionally, the potato is high in carbohydrates and a good source of protein, vitamin C, the B vitamins, potassium, phosphorus, and iron. Most of the minerals and protein are concentrated in a thin layer beneath the skin, and the skin itself is a source of food fiber; health authorities therefore recommend cooking and eating potatoes unpeeled.
The potato grows best in a cool, moist climate; in the United States mostly in Maine and Idaho. Russia, Ukraine, Poland, Germany, and Belarus are the greatest potato-producing countries of Europe, and China and India are now (with Russia) among the top three potato growers. Potatoes are usually propagated by planting pieces of the tubers that bear two or three "eyes," the buds of the underground stems. The plant is sensitive to frost, is subject to certain fungus and virus diseases (e.g., mosaic, wilt, and blight), and is attacked by several insect pests, especially the potato beetle. Potatoes are classified in the division Magnoliophyta, class Magnoliopsida, order Polemoniales, family Solanaceae.
See studies by L. Zuckerman (1998) and J. Reader (2009).