(Editor's Note: This article was originally published on January 23, 2008. Your comments are welcome, but please be aware that authors of previously published articles may not be able to promptly respond to new questions or comments.)
Jerusalem artichokes, also called sunchokes, are often seen growing wild in abandoned old homesteads, meadows and along roadsides. Pick a handful as part of a colorful fall bouquet.
(Photo Thanks to Raggedyann)
Jerusalem Artichoke, Sunchoke
You can grow Jerusalem Artichokes easily in your garden but choose a spot carefully as they can be invasive and easily spread from a tiny piece of tuber left in the ground. They grow up to 10 feet tall with a 4-inch, yellow daisy-like flower from late summer into fall. They are wonderful planted along my fence line.
The tubers look like a ginger root or a knobby potato and vary in color from pale brown to white, red or purple. They are high in potassium and iron, as well as fiber and some B vitamins. "Research has shown that the tubers contain more protein than soybeans, corn, wheat, or beans." 
Cooking Jerusalem Artichokes
Jerusalem artichokes are delicious sliced raw for salads, sautéed, or baked like any root vegetable or winter squash. The tubers are slightly sweet and nutlike tasting somewhat like water chestnuts. They have fewer calories per gram than white potatoes. It is not necessary to peel them (scrub instead) as the skin is edible, just not attractive. They peel easily after steaming or boiling.
The flesh of Jerusalem artichokes will darken with exposure to air just as potatoes or apples will, so if you are serving them raw be sure to dip them in water with a dash of lemon juice or vinegar. Even after cooking, the high levels of iron may cause stored cooked tubers to turn gray, not an appealing result. A pinch of cream of tartar or lemon juice or vinegar in the cooking liquid will remedy this. Add 1/4 teaspoon of cream of tartar or 1 tablespoon of acidic juice per quart of water. The acids will strengthen the texture, so if you want the finished result to be softer, add the acidic juice during the last five minutes. Avoid using aluminum or cast iron pots as these metals will cause oxidation turning the vegetable an unappealing dark color.
Jerusalem artichokes go well with cinnamon, nutmeg, cloves, onion, and cream. They also go well with just about any protein source. Mashed chokes can be used as a thickener for soups and stews. Try them instead of potatoes in a potato pancake recipe. They can usually be substituted for turnips or parsnips. The consistency is like a potato and best steamed to avoid becoming mushy. The tubers store carbohydrate as inulin (not insulin), a source of fructose useful for diabetics. "Jerusalem artichoke flour is also recommended for those who are allergic to wheat and other grains." 
"Jerusalem artichokes can also be used as animal feed. You can feed the leaves, stems and blossoms to your sheep, goats, pigs, and cattle. The leaves and stems contain 28 percent protein. That's more than twice the amount of protein in corn. That's not all. They need little or no fertilizer. They grow so fast that they shade out weeds. They produce large harvests in almost any type of soil - even poor, infertile soils. They grow well with very little water and are resistant to drought. In fact, too much water may reduce growth and rot the tubers. The tubers produce best in temperatures below 28 degrees Celsius (82ºF)." 
Growing Jerusalem Artichokes
The growing requirements are full sun, pH neutral, and they do best in zones 4a to 9b. Water regularly but do not over-water. The plants are attractive to bees, butterflies and birds. Bees are the biggest pollinators. This plant provides food for several caterpillars and beetles. The large nutritious seeds are consumed by various gamebirds, songbirds, and small mammals. Large herbivores, such as cattle and deer, may eat the leaves and flowers. Occasionally the stems are used by muskrats and beavers for their dens or dams.
Propagating Jerusalem Artichokes
You can propagate Jerusalem artichokes by dividing the tubers. Tubers may be purchased at the supermarket or a farmer’s market as well as online. In my area, they are listed for sale in a local trade paper. Over two hundred varieties are now available which are used not only in many commercial products as a fructose source but also to make alcohol. The Jerusalem artichoke has always been cultivated more in Europe than in America.
Plant tubers the same way you would plant potatoes. You can either plant the whole tuber, or you can plant a piece of the tuber which has several eyes. Dig and replant every few years in newly loosened soil. Dig the tubers in the fall and store in high humidity. (Grocery stores often have them in an open shallow pan of water, which I presume is changed daily or so.)
Jerusalem artichokes were a staple of many Native Americans, as they were quite abundant and stored well. This misunderstood tuber’s popularity as a food source has finally reemerged. That this plant also gives us pretty flowers is just a bonus!
There are some Jerusalem Artichoke recipes here
And more here
Thanks to Gabrielle, Poppysue and Frostweed for the photos from Plantfiles.