Kohlrabi is an unusual-looking vegetable with a round root topped by three or more leafy stems. The color of the roots can range from blackish-purple to a cabbage green. The vegetable is best harvested and eaten at around 2 inches in diameter. Larger kohlrabi can develop a thick, woody exterior that will need to be removed before cooking or eating. Kohlrabi can grow to 4 to 5 inches if not harvested at the 2-inch stage.
According to Vegetarians in Paradise, the origins of kohlrabi are lost to history. The first mention of it in European literature is a mention of Corinthian turnip by Pliny the Elder in the first century AD. Pliny the Elder's Corinthian turnip closely resembles the kohlrabi's growth patterns. The author of an Imperial Roman cookbook, Apicius, also mentions kohlrabi in recipes.
Spread Through Europe
As a vegetable known to the Roman Empire, kohlrabi was likely grown in many parts of the Roman Empire. By the year 800 A.D., the Holy Roman Emperor Charlemagne ordered that kohlrabi be grown in Imperial gardens. Although Charlemagne is thought to be French, he was actually from western Germany. The name "kohlrabi" is actually a German name that means "cabbage turnip."
By the 1600s, Kohlrabi had spread to India via trade. By this time, it had become a staple crop in India. It has more recently been cultivated in China and other parts of East Asia, the Middle East and Africa. By the late 20th century, it was grown in many parts of the world, and recipes developed both for the cooking of the root and of the leaves.
Spread to the United States
Although kohlrabi is available in the United States, it is not common outside of the southern U.S. It was first recorded as a crop in the United States in 1806. It is often grown as an exotic vegetable in home gardens and can sometimes be found in some supermarkets. As a member of the cabbage family, kohlrabi can be eaten raw or cooked, depending on the requirements of the recipe.
Chopped kohlrabi is often used in salads or as part of veggie dip trays. The round root of the plant can be hollowed out, stuffed and baked. Kohlrabi greens are often cooked and eaten like mustard or collard greens. The root can also be steamed and served as a side dish, often with carrots.