Growing potatoes is fun as well as practical, thanks to the development of disease-resistant varieties and varieties in a range of colors, shapes, and sizes. Native to the Andes mountains of South America, potatoes thrive in the cool northern half of the United States and the southern half of Canada. Growers in other areas, however, can have successful crops by planting potatoes in very early spring or, in warm regions, in fall or winter for a spring harvest.
Although you can grow some potato varieties from seed, it’s easier to plant certified, disease-free “seed potatoes” purchased from garden centers or Internet and catalog suppliers. (Potatoes you buy at the grocery store are often chemically treated to prevent the eyes from sprouting.) You’ll need 5 to 8 pounds of potatoes to plant a 100-foot row. Along with standards such as ‘Katahdin’, try some colored potatoes like ‘All Blue’, ‘Rose Gold’, ‘Purple Peruvian’, and ‘Cranberry Red’.
Potatoes need space, sunshine, and fertile, well-drained soil. Acid soil provides good growing conditions and reduces the chance of a common disease called scab.
Plant seed potatoes whole, or cut them into good-sized pieces, each of which should contain 2 or 3 eyes. Cure the cut pieces by spreading them out in a bright, airy place for 24 hours, or until they are slightly dry and the cut areas have hardened. In wet climates, some gardeners take the precaution of dusting seed potatoes with sulfur to help prevent rot.
Plant early cultivars 2 to 3 weeks before the last spring frost or as soon as you can work the soil. Time the planting of late cultivars so they will mature before the first fall frost.
Plant potatoes in rows spaced 3 feet apart. Place the seed pieces 6 inches apart, and cover them with 4 to 5 inches of soil. As the vines grow, hill soil, leaves, straw, or compost over them to keep the developing tubers covered. (When exposed to sunlight, tubers turn green and develop a mildly toxic substance called solanine.) Leaving only a small portion of the growing vines exposed encourages additional root development.
Most growers prefer to plant potatoes in hills or in mulch mounds. The mulch-planting method is especially good for growing potatoes in containers, such as large barrels. This “dirtless” method makes harvesting extremely clean and easy but can produce a smaller crop of small tubers.