Cauliflower

Overview

Cauliflower – Brassica olearacea botrytis                               Rotation group - Brassicas

Cauliflowers are a true test of the gardener’s’ skill. They resent any sort of check to their growth. Summer and autumn cauliflowers are the most demanding because they don’t like too much heat and must not go short of water at any time during their growing season. Winter cauliflowers are a little more forgiving and will recover from the occasional setback.

Varieties to choose (as sold by Kings Seeds)

• Snowball AGM (summer and autumn harvesting) - a gardener's favourite that has stood the test of time. Dwarf compact plants that can be set closer than others
• Aviron FI AGM (autumn and winter harvesting) - superb deep large curds with strong leaf growth for light forst protection. Ideal for poorer soils and low in nitrogen cultivation
• Aalsmeer AGM (autumn and winter harvesting) - early vigorous variety with excellent curds that are well protected. Creamy white heads of good depth and weight. Frost hardy

How to grow

Sow

Cauliflowers are grown from seed. Sow the seed of summer and autumn cauliflowers in small pots or trays filled with fresh seed compost during late January in temperatures of 60 F/ 16 C. Prick the seedlings out individually into 3ins/9cm pots filled with fresh potting compost. Grow them on until they have produced four true leaves before planting them out in well prepared soil during April – May at 2ft/60cms between the plants and between the rows

If you are unable to provide any heat the seed can be sown outdoor on a well prepared seed bed during March – April and grow them in the same way as the winter cauliflowers described below .

Winter or more accurately overwintering cauliflowers are sown in the open ground on a well prepared seed bed during April – May.  Sow the seed in 1ins/25mm deep drills, watering along the drills using a watering can containing liquid seaweed to help the germination seeds grow. Thin the seedlings down to 3ins/75mms apart and allow them to grow on until they have produced four true leaves when they will be ready for lifting and transplanting into rows.

Growing on

Water along the row of young plants on the evening before you intend to transplant them. To help the plants move into their new home try to carry the job out during a cool and cloudy period. Water the plants to settle the soil back around the roots and provide the young transplants with some shade on hot and sunny days until they start to produce new leaves. Keep the plants well watered never let them become dry at the roots at any time.

Aftercare

Cauliflowers are hungry plants so water them with liquid seaweed once week during the summer. This will also help them to cope under hot and dry conditions. To help support the growing plants draw soil up around the stalk to just under the leaves. As the white heads/curds begin to swell to stop them turning green; snap and then fold some of the larger leaves over the heads to shade them against strong sunlight.  Also when the cauliflowers are mature the entire plant can be pulled over to face away from the sun to protect the head from direct light.

How to Harvest

Summer and autumn cauliflowers are cut from June until November and the winter cauliflowers can be cut up to end of the year and then left until the Spring. Cut the heads for immediate use or water the plant, dig it up with soil still on the roots and hang in a cool shed or cellar. It should keep like this for several weeks

Issues

Cabbage root fly and cabbage white butterfly are the two main pests. Use 6ins/15cms square mats placed around the stems of the cauliflowers at transplanting time to protect from root fly and cover with horticultural fleece netting to control the cabbage white fly.

Cauliflowers can suffer from club root and a condition known as whiptail if the soil is in poor condition and has a low p.H.