Kohlrabi (Brassica oleracea Gongylodes Group) is a low, stout cultivar of the cabbage which has been selected for its swollen, nearly spherical, Sputnik-like shape. The name comes from the German kohl (cabbage) plus rabi (turnip), because the swollen stem resembles the latter. Kohlrabi has been created by artificial selection for lateral meristem growth, its origin in nature is the wild mustard plant.
The taste and texture of kohlrabi are similar to those of a broccoli stem or cabbage heart, but milder and sweeter, with a higher ratio of flesh to skin. The young stem in particular can be as crisp and juicy as an apple, although much less sweet. Except for the Gigante cultivar, spring-grown kohlrabi much over 5 cm in size tend to be woody, as do fall-grown kohlrabi much over perhaps 10 cm in size; the Gigante cultivar can achieve great size while remaining of good eating quality.
There are several varieties commonly available, including White Vienna, Purple Vienna, Grand Duke, Gigante (aka "Superschmeltz"), Purple Danube, and White Danube. Coloration of the purple types is superficial: the edible parts are all pale yellow.
Hamburg Township, Michigan has titled itself the "Kohlrabi Capital of the World" and at one time had a kohlrabi festival which drew 600 people at its peak in 1985 [1]
Some varieties are grown as feed for cattle!
How to Eat Kohlrabi
The best way of all is raw – peel them and slice thinly then eat. They beat most other raw vegetables hands down.
At Greenfield Village, heirloom White and Purple Vienna kohlrabies are grown and prepared as they were in the late 1800s -- peeled, then sliced and fried or boiled and mashed with butter salt and pepper. In "The Victory Garden Cookbook" (Knopf, $39.95), Marian Morash says kohlrabi has better flavour if the skin is left on during cooking.
Kohlrabi can also be steamed or boiled. Don't peel until after they are cooked. Steam or boil until bulbs are tender, peel skin, and season with butter, salt, and pepper, a cheese sauce, or just enjoy plain.
If the leaves attached to the kohlrabi bulb are fresh and green, they can be enjoyed as a cooked green. Wash the leaves and remove the ribs. Blanch in boiling water until just wilted, 3 to 5 minutes. Drain and squeeze excess water from leaves. Chop leaves, then saute in a little olive oil or butter. Season with salt and pepper. Add a splash of vinegar or squeeze of fresh lemon juice.
They can be added to a vegetable soup or hollowed out, stuffed (vegetarian or carnivorous) and baked