Kohlrabi

• 1. Introduction

  ›

  Kohlrabi looks like a vegetable that cannot decide what it is. The swollen, nearly spherical stem sits low to the ground, sprouting leaves on thin stalks, earning it two contradictory nicknames at once: German turnip and turnip cabbage. Its scientific name is Brassica oleracea, Gongylodes Group. That Group name comes from the Greek gongylos, meaning round. Yet despite the turnip in its names, it is not a turnip at all. It is not a rutabaga either. It is something stranger and more deliberate, a plant shaped by human hands toward a single odd goal. So where did this round, pale stem come from? Why does a botanist writing in 1554 say it had only lately arrived? And why does a vegetable best known in Europe sit at the heart of dishes cooked in Kashmir, Cyprus, and Vietnam? The answers begin with a plant that, by birth, was never supposed to be round at all.

• 2. One Plant, Many Faces

  ›

  Brassica oleracea is one species wearing many costumes. Kohlrabi shares it with cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens, Savoy cabbage, and gai lan. All of them descend from the same ancestor, the wild cabbage plant. What separates kohlrabi from its siblings is what humans chose to enlarge. Through artificial selection, growers pushed the plant toward lateral meristem growth, swelling the stem into its rounded form. Broccoli was bred for its flower buds and kale for its leaves, but kohlrabi was bred for that bulbous stem above the soil. The origin in nature is identical across the whole family. Only the destination differs. This shared parentage explains a quiet fact of the kitchen: kohlrabi tastes much like a broccoli stem or a cabbage heart, only milder and sweeter. The plant is, in a sense, a cabbage that grew sideways on purpose.

• 3. A Name Built From Two Roots

  ›

  The name kohlrabi is a small piece of German welded together. It joins Kohl, meaning cabbage, with Rübe, meaning turnip, rendered as Rabi in a Swiss German variant. The word exists because the swollen stem resembles a turnip, so people described the plant as a cabbage-turnip and the label stuck. That borrowed resemblance has caused lasting confusion, since the names insist on a turnip kinship that the biology denies. Both turnip and rutabaga belong to the genus Brassica, which keeps them in the same broad neighborhood. But neither shares kohlrabi's species. The Group name Gongylodes settles the matter differently, describing not what the plant resembles but what it simply is: roundish.

• 4. Lately Into Italy

  ›

  In 1554 the botanist Mattioli set down the first European written record of kohlrabi, noting that it had come lately into Italy. That single phrase marks the plant's entrance onto the written page. From there it traveled fast. By the end of the 16th century kohlrabi had spread to North Europe and was being grown across a wide arc of the map: Austria, Germany, England, Italy, Spain, Tripoli, and parts of the eastern Mediterranean. A vegetable barely worth recording in the middle of the century had become a regional staple within a few decades. Its German name would follow it everywhere it went, carrying the memory of where it caught on first.

• 5. The Shape Of A Good Bulb

  ›

  Size is the enemy of a good kohlrabi. Spring-grown stems much over 5 centimeters tend to turn woody, and full-grown ones much over perhaps 10 centimeters do the same. The exception is the Gigante cultivar, also known as Superschmelz, which can reach great size while keeping good eating quality. A typical plant weighs roughly 150 grams and matures in 55 to 60 days after sowing, then holds its standing ability for up to 30 days past maturity. The young stem at its best is as crisp and juicy as an apple, though far less sweet, with a high ratio of flesh to skin. Gardeners can choose from several named varieties: White Vienna, Purple Vienna, Grand Duke, Gigante, Purple Danube, and White Danube. The purple coloring is only skin deep. Cut any of them open and the edible flesh is pale yellow throughout. One variety abandons the bulb entirely, growing just leaves on a very thin stem, and is called Haakh. In its second year the plant stops feeding the bulb and turns instead to blooming and setting seed.

• 6. The Trouble With Peeling

  ›

  A kohlrabi promises more than it delivers. The enlarged stem is wrapped in two distinct fibrous layers that refuse to soften no matter how long they cook. Cooks peel these away before serving, raw or cooked, so the trimmed stem yields a smaller amount of food than its intact bulk suggests. What remains is worth the work. The bulbous stem is the part most often used, sliced thin and eaten raw in salad or slaw, crunchier and crisper than a raw broccoli stem and sweeter besides. The leaves are edible too, treated much like collard greens and kale, though they take longer to cook. By weight the raw stem is mostly water, about 91 percent, with 6 percent carbohydrates, 2 percent protein, and almost no fat. A 100 gram serving supplies 27 calories and a strong dose of vitamin C, around 65 percent of the Daily Value, plus moderate copper and potassium.

• 7. From Kashmir To Hanoi

  ›

  In Kashmiri kitchens kohlrabi is called Monji, and it ranks among the most commonly cooked vegetables there. It is prepared with its own leaves, served in a light soup, and eaten with rice. The leafy, bulb-free variety, Haakh, gives its name to a companion dish, and both Haakh and Monj are popular Kashmiri preparations of the plant. Far to the east, kohlrabi turns up across Vietnamese cuisine, appearing in nem ran, in stir fry, and in canh. Sliced thinly, the raw stem goes into nom or is dipped in nuoc cham. In Cyprus the approach is simpler still: the vegetable is sprinkled with salt and lemon and served as an appetizer. Not every kohlrabi reaches a human plate. Some varieties are grown as feed for cattle, and the plant takes well to hydroponic systems, producing a large edible mass without clogging the nutrient troughs that carry its water.