Kohlrabi is a tall, erect perennial herb that is native to southern Asia, and it has been used as a medicinal crop in India, China, Korea and other Asian countries for hundreds of years. Kohlrabi, Brassica verosa, is a naturally occurring herbaceous perennial found for its edible fleshy stem. The kohlrabi plant usually has an upright stem that is bushy at the top, closely resembling a turnip. The leaves are needle-like with a long base and the flower buds are spiny.
Kohlrabi is a very tough plant, but it is easily grown from cuttings taken during the summer months. The hardy variety is cultivated for its edible root which can be eaten raw or cooked. The Brassica oleracea or kohlrabi contains an acid that causes the plant to produce the edible stalks. It can be easily grown in moist soils.
Kohlrabi is a perennial plant that is widely grown both for ornamental purposes and for culinary uses. Plants range in height from six to twelve inches. Flowers are blue and the roots bear red berries. Flowers and leaves appear to grow in clusters. Kohlrabi bulbs can be found in a variety of colors, shapes and sizes. Kohlrabi flowers are about one inch long while the leaves are about two-thirds this size.
To assure a healthy yield, it is important to provide consistent growing conditions, especially during the growing season. During the summer, it is important not to over water the plants because they tend to drown in the standing water. When growing kohlrabi for culinary use, it is important to protect the roots by keeping them well watered when the soil is dry. During the winter season, it is best to move the plants indoors to prevent frost from setting in.
Full sun is the optimum growing condition for kohlrabi plants. In the southern United States, the plants have been found growing in states with less than 40% humidity. Because the plant likes full sun, it is important to place the garden in a spot that gets at least six hours of sunlight. Although there are now many varieties of shade-loving plants available, the preferred shade loving plant is the Kohlrabi.
As with other cool-season crops, proper irrigation is important. Watering should be done carefully and only after the soil has dried completely. Pots should be filled with clean water and turned often to ensure that the water drips from the soil and goes into the pot. If the roots of the plants are damaged, the soil can be sprayed with a weak solution of 2 tablespoons of bleach per gallon of water. Once the leaves on the plant start to turn yellow and the quality of the crop suffers, this should be avoided. Pests like aphids love growing on the plant, so spraying them with a weak solution of borax will discourage insects from growing on them.