The vegetable commonly known as cabbage is actually one of several forms of a large group known collectively as cabbages. The cabbages are raised as ornamental plants as well as food for livestock and for humans. The different forms of cabbages include kale, broccoli, cauliflower, brussels sprouts, kohlrabi, and head cabbage.

Where cabbages grow

Cabbages are one of the oldest vegetables grown for human food. Wild cabbages originally came from the shores of the Mediterranean Sea in Western Europe. They also grow on the sea cliffs of Great Britain, where they were probably introduced by the Romans. Today cultivated plants like head cabbage, which are descended from these wild cabbages, are grown in mild climates throughout the world. Successful cultivation requires a cool growing season and deep, fertile soil. These plants tolerate hard freezing at certain periods of their growth, but none of them do well in hot weather.

Physical features

The flowers of cabbages have two separate petals and two sepals, which are petal-like parts, arranged in opposite pairs in the form of a cross. The flowers may be white, yellow, orange, lilac, or purple, arranged in loose clusters at the top of the stem. All members of the group have leaves covered with a waxy coating. This waxy coating often gives the leaf surface a gray-green or blue-green color.

Cabbages can be classified according to which part of the plant is used for food and how that part is structured. In some forms it is the leaves that are eaten. Kale has loose leaves that spread outward from a stalk. Head cabbage has tightly folded leaves that form a single large head around a stem. Brussels sprout plants form many little heads called brussels sprouts about 1 to 2 inches (3 to 5 centimeters) in diameter along the tall, sturdy stem instead of one large head at the top. In other kinds of cabbages, such as broccoli and cauliflower, the thickened flowers of the plant are consumed. Kohlrabi has a thickened stem that is eaten.