Family: Brassicaceae
Common name: Kohlrabi, Cabbage Turnip, German turnip, Knol-Knol, Turnip cabbage, Nukol, Ol kobi, Gadde kosu, Turnip kale, Knol, Kaalrabbi
Kohlrabi is a versatile and widely used vegetable, a cultivar of the Wild Cabbage which is the mother of many vegetables like cabbage, broccoli, turnips, Brussels sprouts, etc. The edible, swollen stem often called the bulb is eaten all over the world, loved for its mild flavor and crisp texture.
Plant characteristics
Root system of the Kohlrabi is quite small and weak, making them easy to harvest. The most interesting and useful part is the base of its stem, which gets swollen and bulbous with leaves radiating from it.
Kohlrabi bulbs can grow to about 10 cm in diameter, similar to a turnip or radish. Though the plant is called Cabbage turnip, it resembles the turnip more than the cabbage.
The skin of Kohlrabi is quite thick and must be peeled off before it is eaten. It can be eaten raw, grated, or sliced and added to salads; or steamed and cooked for various dishes.
The most common variant of Kohlrabi has a light green bulb, but there is a variant with purple bulbs as well, but the inside of it is yellowish-green.
Kohlrabi leaves are broad and green, growing from the sides and the top of the swollen stem or bulb. They are 25-35 cm long with a thick, waxy coating to prevent water damage since the leaves grow very close to the ground.
These leaves are lobed with jagged edges, and the purple variant has green leaves with purple hues. Kohlrabi leaves are edible and can be consumed raw or cooked.
Like other members of the Wild cabbage family, Kohlrabi plants produce small, four-petaled flowers in clusters, on top of long stalks.
These flower stalks emerge from the center of the bulb if it is left unharvested. They are 1-1.5 cm in diameter and not particularly showy, but they can attract pollinators with their bright colors.
After pollination of the flowers, they produce elongated seed pods that contain tiny, rounded seeds. Kohlrabi seed pods are 3-4 cm long, misshapen, and bulbous where the seeds are. They are green and flexible initially, turning brown on maturity when they open up to release the seeds.
The name Kohlrabi comes from different languages – Kohl which is German for cabbage, and Rabi which is Swiss for turnip. The variant name gongylodes comes from gongýlos which means rounded in Greek.
Gardening tips
Kohlrabi plants need bright sunlight through most of the day, and well-drained soil. Since the base of their stem becomes rounded and bulbous, waterlogging or overwatering can lead to stem rot and damage.
They need regular watering and fertilization, since these plants are short-lived, completing their life cycle in a year or so.
Plant Kohlrabi about 60 cm away from each other to make sure that the leaves have enough space to grow and spread in a rosette pattern. These plants are susceptible to aphids, worms, and mealy bugs, which can be kept away by neem oil or insecticidal soaps.
Kohlrabi plants can be easily grown in home gardens in reasonably large pots and harvested quickly. These plants are closely related to Cauliflower or Brassica oleracea var. botrytis, Cabbage or Brassica oleracea var. capitata, Brussels sprouts, Turnips, Savoy cabbages – all those yummy variants of the Wild cabbage.
Uses of Kohlrabi
Kohlrabi is mostly water (92%) with carbohydrates and proteins in small amounts. They contain a good helping of Vitamin C, and moderate quantities of Copper, Potassium, and other micronutrients.
The leaves are also rich in calcium, iron, and potassium. Kohlrabi is good for digestion since the high water content prevents constipation and improves gut health.
The leaves are cooked and eaten as vegetable, though they have to be picked when the leaves are tender. Stems or bulbs are eaten raw or cooked, used in a wide variety of dishes. They are very popular in Kashmiri cuisine, and also a common ingredient in Vietnamese cuisine.
Propagation
Propagation is through seeds, which can be collected from mature plants that have brown seedpods. Sow the seeds in moist soil for them to germinate.
Photographed at: Acharya Jagadish Chandra Bose Indian Botanic Garden, Howrah
