The potato is a starchy, tuberous crop from the perennial nightshade Solanum tuberosum. The word "potato" may refer either to the plant itself or to the edible tuber. In the Andes, where the species is indigenous, there are some other closely related cultivated species. Potatoes were introduced outside the Andes region approximately four centuries ago, and have since become an integral part of much of the world's food supply.
Andes MOUNTAIN RANGE
Potato plants are herbaceous perennials that grow about 60 cm (24 in) high, depending on variety, with the leaves dying back after flowering, giving fruit and tuber formation. They bear white, pink, red, blue, or purple flowers with yellow stamens. In general, the tubers of varieties with white flowers have white skins, while those of varieties with colored flowers tend to have pinkish skins.
Potatoes are mostly cross-pollinated by insects such as bumblebees that carry pollen from other potato plants, though a substantial amount of self-fertilizing occurs as well. Tubers form in response to decreasing day length, although this tendency has been minimized in commercial varieties.