Brassica oleracea, Gonylodes group is a member of the Brassicaceae (mustard) family.

Varieties include White Vienna, White Danube, Green Vienna, Purple Vienna, Purple Danube, Earliest Erfurt, and Grand Duke.

Cabbage-like leaves on long stems arise from the top and sides of the round, root-like stem. Also called stem turnip because of the turnip like enlargement of the stem 1 to 3 inches above the ground. Leaves grow up to 10 inches long. It is a low biennial plant native to northern Europe. Two types are available, those with green and purple skins. The flesh is always white.

Marketing. Baby kohlrabi is tender and the greens are good tasting. This crop can be sold as a baby vegetable at one to two and a half inches in diameter, or as an adult at about fist sized. The baby is used whole, cooked or sliced in salads. The greens are also valued at this stage. The greens of the adult are too tough. The plant can not easily be sold at the intermittent size. Red or purple varieties are almost unknown as adults in the market, but they produce better greens than the green types.

Harvest with clippers. Do not bunch as the leaves bruise and break. They keep well in transit if not packed too tightly. No standard pack.

Use. Generally before the kohlrabi stem is eaten, the peel is removed and the interior is diced and boiled. The swollen stem may also be eaten raw when young; it is crunchy and can be served in salads, or with dips. The young, tender leaves are edible raw or steamed. The enlarged stem is essentially used the same as turnips. It should be used when the tubers are 2 to 3 inches in diameter, before they become hard and bitter. Stress also causes the stems to become fibrous and woody.

Nutrition. A good source of vitamin C and potassium.

Climatic requirements. Common varieties of kohlrabi may sprout unwanted seedstalks if grown for over a week in cold temperatures of 50° F (10° C). Recommended temperature range is 65 to 77° F (18 -25° C) with 72° F (22° C) being optimum. Cold spells of temperatures in the 20°s F will kill or stunt the plants.

Propagation and care. Propagation and time of planting is similar to cabbage; it is grown the same as turnips. Plant spacing is about 4 inches in rows 18 to 20 inches apart. It can also be planted with two rows on a 36 inch by 40 inch bed, 4 inches between plants. Plant seeds approximately 1/2 inch deep. Kohlrabi matures in about 60 days when started from seeds, and 40 days started from transplants; however, transplanting may hurt development of the stems. Pests are those of the cabbage. There are green and purple or red cultivars.

Harvest and postharvest practices. USDA storage recommendations are 32°F (0°C) at 98 to 100 percent relative humidity, with an approximate storage life of 2 to 3 months.

Kohlrabi seed is widely available.

Compiled by Claudia Myers, UC Small Farm Center and Keith Mayberry, Farm Advisor, Imperial County.

Reviewed by Harold Otto, Orange Co. 12/15/89.

Reviewed by Keith Mayberry.

Reviewed by John Guerard, Farm Advisor, Kern County, 12/22/89.

Reviewed by Yvonne Savio, 12/27/89.

Captions:

Figure 1. Kohlrabi is grown for the enlarged stem which is generally eaten when it is 2 to 3 inches in diameter, before it becomes hard and bitter. This is the White Danube variety. (Photo curtesy of Sakata Seed Co.)

Figure 2. Purple Danube kohlrabi variety. (Photo curtesy of Sakata Seed Co.)

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