Kohlrabi Brassica oleracea

Ornamental cabbage is the wild ancestor of a group of annual cool weather vegetable plants including kale, collards, broccoli, cauliflower, and kohlrabi.  These crops are referred to as Cole Crops.  Ornamental cabbage is in the Brassicaceae (mustard) family. The genus name Brassica is Latin for cabbage, while oleracea means vegetable/herb. These plants are grown for their edible leaves. In its native habitat, it can be found growing along coastlines on rocky sea cliffs in Western Europe.  

It can grow in a wide range of conditions, however, and will perform at its best when located in full sun in nitrogen-rich, alkaline soil with good drainage. After flowering, cut out the flowering stems when the flowers show signs of forming seed pods. That will conserve the plant’s energy or resources for additional leafing up. Propagate by seed or stem cuttings. 

The foliage of ornamental cabbage is fleshier and thicker than other Brassica species. That gives it an edge in difficult growing conditions, allowing the foliage to store water and nutrients. It forms a loose head of large green or blue-green leaves that are edible.  They can be boiled or steamed until tender. 

Ornamental cabbage will grow in a container and is as at home in a meadow or pollinator garden as it is in an edible garden. It can be used in a border or a mass planting. 

Insects, Diseases, and Other Plant Problems: Enlargement of the thyroid gland can occur if consumed in large quantities. In locations where full sun is not provided, downy mildew can form. Some pests affecting this plant include slugs, snails, aphids, and white caterpillars.

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common Cole crop diseases and other plant problems.

VIDEO Created by Elisabeth Meyer for "Vegetables, Herbs, Fruits, and Nuts" a plant identification course offered in partnership with Longwood Gardens.