Vegetable brassica types

Head Forming Cabbages (Brassica oleracea L. (Capitata group) and Brassica rapa subspecies)

Cabbages are grown as an annual crop. Plants are usually raised and then transplanted in beds in the field. Basal leaves can be up to 25cm or more long and wide, and spreading in nature. As the crop matures, the ‘head’ is formed - consisting of the ‘core’ or stem terminal and densely packed leaves. At harvest, or prior to eating, the coarser tasting outermost leaves that encircle the head are removed. Heads vary from 10 to 30 cm or more in diameter and, according to type, are round, or cone shaped.

There are a wide range of head forming cabbages: 

• Green cabbage (Alba subgroup) – with a tight head of pale green or almost white leaves. These types are used for cooking (largely boiling), sour cabbage (sauerkraut) or salads such as coleslaw. 
• Red cabbage (Rubra subgroup) – a purplish red cabbage that adds interest to salads. 
• Savoy cabbage (Sabauda subgroup) - with crinkle leaves in a loosely compact yellow-green oval head. This cabbage is tender and mild and suited for cooking as well as salads. 
• Chinese cabbage (Brassica rapa var pekinensis) - a sweeter and milder cabbage than the traditional head cabbage with thin, crisp, crinkly, cream coloured leaves. 
• Pak choy (Brassica rapa var chinensis) - also called Chinese white cabbage has long mild white stalks topped with green leaves.

Brussels Sprouts (Brassica oleracea L. Gemmifera group)

This plant of the cabbage family attains a height of up to one meter. The edible parts are small, very compact, 2-5cm diameter heads or "sprouts" that grow in the axils of the leaves along the stem. Sprouts are tightly packed leaves around a core and resemble miniature cabbage heads.

Cauliflower (Brassica oleracea L. Botrytis group)

Cauliflower is grown as an annual crop for the edible, partially developed, multiple flower head. It develops large basal leaves which surround but do not completely cover the head which is borne terminally on the stem. Since a white head is desired, varieties have been developed that have sufficient leaf cover to protect the head and aid blanching. Heads are harvested while still compact, white and firm.

Broccoli (Calabrese, Brassica oleracea L. Italica group)

The broccoli plant is a strong growing, upright annual, up to 1m in height, with large spreading leaves. The edible portion is the immature flower head which is cut when the floral buds are small and green. The central head may be 7 to 20cm across and rather flat. It is commonly cut with a 15-20cm stem.

Kale (Brassica oleracea L. var sabellica - Acephala group)

Kale grown for food is handled as an annual, although the plant is biennial. Most varieties have very curled grayish-green thick smooth leaves. They can be grown for summer or winter production. The whole plant is cut off and trimmed before selling.

Kohlrabi (Brassica oleracea L. Gongylodes group)

Kohlrabi is a cabbage relative, grown for the turnip-like enlargement of the stem just above ground level. Plants are commonly transplanted and must be grown rapidly to provide good quality ‘bulbs’. Leaves rise from the enlarged globe-like or flattened bulb which is usually 5-8 cm in diameter at harvest.