Jerusalem Artichoke, Red ($1.50 per medium tuber)
Jerusalem Artichoke, aka sunchokes, topinambours, and a few other names. This is the red variety. Jerusalem artichokes are in many ways the perfect food plant. Native to much or North America, perennial (difficult to eradicate, in fact: plant in its own area, it will spread and can get weedy), no-maintenance, and even ornamental, with yellow flowers in late summer. Tall (up to 10 feet, but usually closer to 6), it produces large, nutritious tubers. One pound of the red variety can turn into 5-6 pounds under the right conditions (light soil, plenty of sun and water). $1.50 per medium tuber.
Cultivation: About the easiest garden plant imaginable. It was widely used as a survival plant in much of Europe for that reason. No known pests (except perhaps for rodents who occasionally rob the tubers), drought hardy (within reason), prolific, happy in just about any soil type (but does better and is easier to harvest in a rich, sandy loam). Stems and leaves can even be used as forage for animals. Groundhogs and rabbits are particularly fond of it!
Food preparation: Countless ways to prepare, especially if you look for French recipes (under the name topinambours). We find it best slow-braised with garlic, or in stews and mashes, mixed with other root vegetables. It works great in a hearty lamb stew for instance, where the sometimes dominant artichoke aroma gets blended nicely with the meaty lamb flavour.
Ethnobotany: Widely used by North American native peoples, it is still abundant in the wild. The wild form typically has smaller tubers, but some can get quite large. It has a long history in Europe where it was introduced in the 1600s. It has both a somewhat lowly reputation as starvation food, because of its common use during the postwar years, and as a delicacy, often found on the menu of fine restaurants.