Kohlrabi

Lore & Background

The name comes from the German Kohl ("cabbage") plus Rübe ~ Rabi (Swiss German variant) ("turnip"), because the swollen stem resembles the latter. Its Group name Gongylodes (or lowercase and italicized gongylodes or gongyloides as a variety name) means "roundish" in Greek, from gongýlos (γογγύλος, 'round'). Kohlrabi has been created by artificial selection for lateral meristem growth (a swollen, nearly spherical shape); its origin in nature is the same as that of cabbage, broccoli, cauliflower, kale, collard greens, and Brussels sprouts: they are all bred from, and are the same species as, the wild cabbage plant (Brassica oleracea). 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.

Reader's Guide

Kohlrabi is significant as a distinctive cultivar of wild cabbage, developed through artificial selection for its swollen stem. It is used in diverse cuisines: in Kashmiri cuisine it is called Mŏnji and is commonly cooked with its leaves; in Cyprus it is served as an appetizer with salt and lemon; and in Vietnamese cuisine it appears in dishes such as nem rán, stir fry, and canh. The plant matures in 55–60 days and can be grown in hydroponic systems. Several varieties exist, including 'White Vienna', 'Purple Vienna', 'Grand Duke', 'Gigante', 'Purple Danube', and 'White Danube'. The purple types have only superficial coloration; the edible parts are pale yellow. The leafy greens are also edible, and a variety called Haakh grows without a swollen stem. Some varieties are grown as cattle feed.

Did You Know?

• Kohlrabi is a cultivar of the same species as cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens, Savoy cabbage, and gai lan.
• The Gigante cultivar can achieve great size while retaining good eating quality, unlike most spring-grown kohlrabi over 5 cm in size.

Botanical Classification & Anatomical Placement

Kohlrabi occupies a precise position within the broader taxonomy of root vegetables. It is classified as a true root, specifically a taproot, which distinguishes it from the many other underground plant parts that fall under the culinary umbrella of root vegetables. In agricultural and culinary terminology, this category encompasses not only genuine roots like taproots and root tubers but also non-roots such as bulbs, corms, rhizomes, and stem tubers. Within the true root category, kohlrabi is grouped alongside rutabaga and turnip, all three belonging to the Brassica species. Some taproot types may incorporate substantial hypocotyl tissue, adding a layer of anatomical nuance to what is otherwise a straightforward classification. This placement as a genuine root—rather than a modified stem, bulb, or corm—sets kohlrabi apart from vegetables like potato, taro, or ginger, which are stored in entirely different anatomical categories within the root vegetable family.

Energy Storage & Carbohydrate Function

As a member of the root vegetable group, kohlrabi functions primarily as an energy storage organ for the plant. Like its fellow root vegetables, it accumulates carbohydrates in the form of starches and sugars, serving as the plant's underground reservoir of metabolic fuel. This biological role translates directly into its value as a food source for humans and other animals. The carbohydrate content is what makes root vegetables broadly significant in human diets, providing dense caloric energy that can sustain populations through periods when above-ground crops are unavailable. Within the Brassica group, kohlrabi shares this fundamental storage function with rutabaga and turnip, all three relying on their taproot structures to sequester these energy compounds beneath the soil surface, making them a reliable caloric contribution across diverse eating traditions.

Storage & Winter Utility

One of kohlrabi's most practical attributes, shared across the root vegetable category, is its capacity for extended storage after harvest. Root vegetables in this category are well suited to root cellar conditions, where they can remain in good condition for a span of several months following the growing season. This preservation capability is particularly significant in nontropical latitudes, where winter traditionally represents a period of little to no fresh harvesting. For communities in these regions, the ability to store root vegetables through cellaring provides a critical nutritional bridge between the active growing season and the cold months when fresh produce is scarce. Additionally, modern season extension methods—most notably the use of polytunnels—can stretch the harvest window further into the winter months, supplementing traditional cellar storage and helping to ensure a more continuous supply of these underground crops throughout the year.

Agricultural & Economic Context

Kohlrabi's placement within the Brassica species and its grouping with rutabaga and turnip situates it within a family of root vegetables that carry considerable agricultural weight. Starchy root vegetables hold particular economic importance as staple foods, a role that is especially pronounced in tropical regions where they can overshadow cereals in dietary significance. While kohlrabi's specific economic profile is not detailed separately from its Brassica relatives, it participates in the broader category of underground plant parts that feed both humans and other animals. The classification system that places it among true taproots—distinct from corms, bulbs, rhizomes, and tuberous stems—reflects the diversity of strategies plants have evolved to store energy below ground, each strategy yielding different agricultural and culinary applications across the world's food systems and contributing to the rich variety of root vegetables available to growers.