Family: Brassicaceae
Binomial name: Brassica oleracea var. gongylodes
Life Cycle: Biennial (usually grown as an annual)
Kohlrabi can be grown year-round in most climates. Avoid planting in extremely hot or cold weather which can affect germination and growth. Use the table below to identify the best time of year to sow kohlrabi in your climate.
JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Cool | ||||||||||||
Temperate | ||||||||||||
Sub-Tropical | ||||||||||||
Tropical | ||||||||||||
Arid |
Kohlrabi plants are best grown in full sun or part shade. Choose a location that will receive at least 3 hours of full sun each day.
Kohlrabi plants need a well drained soil enriched with plenty of organic matter. Prepare soil by weeding it thoroughly, digging it over to loosen it and adding aged animal manure or compost. Keep the area free of weeds until planting.
Kohlrabi plants can be grown in containers. If possible choose a variety that’s recommended for container growing. Use a good quality potting mix and make sure your container is large enough for mature plants; a minimum of 40 litres is recommended for kohlrabi. During the growing season, keep in mind that container grown plants may need additional fertiliser to encourage healthy growth.
Kohlrabi seeds do not require any treatment (eg soaking, stratification) before sowing.
Kohlrabi seeds grow best when they are sown directly into the garden.
Kohlrabi plants may need watering during the growing season. Water when the soil is dry about 5cm below the surface (test this by scratching away a little soil with your finger). Water deeply in the early morning or late afternoon. Avoid watering the leaves of plants to avoid fungal diseases. Learn more about watering here.
If soil was well prepared no extra fertiliser should be necessary. In poor soil or to give your plants an extra boost, application of a balanced fertiliser or one formulated for fruit and vegetables can be beneficial:
Kohlrabi should be ready to harvest in approximately 55-70 days.
Leaves are ready to harvest when they are large enough to eat, and can be harvested as needed. Harvest leaves by pinching off the outer leaves, leaving some on the plant for future growth. Eat kohlrabi leaves as soon as possible after harvesting. Store leaves short term in a perforated plastic bag in the fridge.
Stems are ready to harvest when they are large enough to eat, and can be harvested as needed. Harvest individual stems by cutting them just above ground level. Cut the foliage 1-2cm above the top of the stem. Store kohlrabi in a perforated plastic bag in the fridge. For longer term storage, kohlrabi can be pickled or blanched and frozen.
Like all plants, kohlrabi is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing kohlrabi plants: