Sunchokes are, in fact, just a little too vigourous for most gardeners. Some varieties will grow as tall as twelve feet, and large plants will quickly grow and spread from any piece of tuber left in the ground (or the compost bin). However, a contained planting of this vegetable will provide a large, low-maintenance harvest year after year, as well as a lovely display of yellow sunflowers.
Sunchoke tubers should be planted about twelve to eighteen inches apart, about four inches deep, and any piece with an eye on it will grow. The tubers should be harvested each year, leaving a few in the ground to grow next year, or the plants will soon become less productive. They can even be hilled, like potatoes, to increase yields. Harvesting usually begins in August (depending on the cultivar) and continues until the ground freezes, although the flavour is thought to be best after frost. Tubers should not be allowed to dry out in storage, but can be frozen, refrigerated, kept in a root cellar, or left in the ground to be harvested in the spring.
Sunchoke tubers can be eaten raw or cooked; roasted, mashed or steamed. Many named varieties exist, with smaller, bushier plants, and larger, smoother tubers than the species, but they can be difficult to obtain. Johnny's Selected Seeds currently carries a variety called 'Stampede' with large tubers and early flowers.