The kolhrabi (Brassica oleracea) is a form of cabbage of European origin. First described in the 16th century. Popular in some areas in the US as a kitchen garden vegetable, but seldom grown for commercial purposes. Grown in Europe as a stock feed.
Easier to grow than broccoli, slightly harder than cabbage. To get tender, sweet kohlrabi, pick them when they are less than 2-2.5 inches in diameter. Fall grown kohlrabi may be kept until they reach a diameter of 4-5 inches.