Knol khol, also known as Kohlrabi, is a versatile and nutritious vegetable that belongs to the Brassica family. It is grown for its edible bulbous stem, which has a mild and slightly sweet flavor. Knol khol is popular in various cuisines and can be eaten raw or cooked.
Botanical name: Brassica oleracea var. gongylodes
Plant morphology: Knol khol has a unique appearance, resembling a cross between a cabbage and a turnip. It has a round or slightly flattened bulbous stem that grows just above the ground. The stem is surrounded by several layers of leaves, which are usually green or purple. The leaves are lobed and have a slightly rough texture.
Common names: Knol khol (English), Kohlrabi (German), Nookal (Hindi), Navalkol (Tamil), Monj (Bengali), Navil Kosu (Kannada)
Soil and climatic requirements: Knol khol prefers well-drained soil with a pH range of 5.5 to 7.0. It grows best in cool climates with temperatures ranging from 18°C to 25°C. It can tolerate light frosts but is sensitive to extreme heat.
Crop duration: 55-60 days
Cropping season: Knol khol is a cool-season crop and is usually grown in spring or fall. It can be grown year-round in regions with mild climates.
Planting type: Direct sowing or transplanting.
Spacing: Plant knol khol seeds or seedlings about 20-30 cm apart in rows that are spaced around 45-60 cm apart.
Depth of sowing: 1-2 cm
Germination period: 4-7 days
Hours of sunlight required: Knol khol thrives in full sunlight but can tolerate partial shade.
Watering: Regular watering is essential to keep the soil evenly moist. Avoid overwatering, as it can lead to root rot.
Companion crops: Knol khol can be planted alongside other cool-season vegetables like lettuce, spinach, and radishes.
Harvesting: Knol khol bulbs are ready to be harvested when they reach a diameter of about 5-10 cm. Harvest them by cutting the stems just above the ground level. The leaves can also be harvested and used in cooking.
Problems of knol khol cultivation:
Pests: Cabbage worms, aphids, and flea beetles.
Diseases: Clubroot, powdery mildew, and black rot.
