The Greeks were cultivating cabbages as early as 600 BC and believed it was a gift from the gods. Over the years, the plant has been used to treat stomach problems, headaches, hangovers and even deafness.Today, cabbages are grown around the world and are one of the most popular vegetables in South Africa. The main production areas are in Mpumalanga and the Camperdown and Greytown districts of KwaZulu-Natal.
Cabbages grow best in a relatively cool and humid climate. Drier conditions affect the quality of the head and leaves, and lead to a loss of flavour. The ideal temperatures for growth and development range from 18°C to 20°C. But cabbages are fairly resistant to frost and can survive temperatures as low as -3°C without damage.
Water requirements vary from 380mm to 500mm per crop, depending on climate and length of growing season. Crop water-use increases during the growing period and peaks towards the end of the season. Cabbages can be grown in a wide range of soils, but thrive on well-drained, moisture-retentive loamy soils with plenty of organic matter. Highly acidic soils are best avoided.
The ideal soil pH ranges from 5,5 to 6,5 and should not be allowed to fall below 4,5. In soil with a pH above 6,5, the leaves become dark, but leaf margins die back. Plants in saline soils are highly susceptible to blackleg. In the next issue, we will provide some cultivation tips.
The cabbage plant
Roots: Adventitious root system. Instead of emerging from a main or tap root, these roots originate from the stem.
Stem: An unbranched stem less than 30cm long.
Leaves: A rosette or circular arrangement of sessile leaves around the growing point (these leaves have no stems and are connected directly to the plant). The outer leaves are green, and the inner ones white. As the plant grows, the leaves increase in number, forming a ball-shaped ‘head’ in the centre of the plant.
Cultivars: Cabbages can be grouped according to the shape of the head – conical-headed (also called sugarloaf-headed), ball-headed or drum-headed. They can also be classified according to their colour and growth cycle. The leaves may be green or red, smooth or wrinkled.
Source: Production Guidelines for Cabbage, Department of Agriculture, Directorate Plant Production.