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Cauliflowers

Cauliflowers are probably the most difficult of the Brassicas to grow although they still fairly easy to grow if the correct conditions are met. The great thing about them is that by using different varieties, you can have Cauli's at any time of the year.

They need a firm, well-drained, fertile soil. A site that has been used for a previous crop that has been manured is ideal. They also need a pH of 6.5 - 7.0, so it is wise to check this and apply lime if necessary. Apply a general fertiliser at the rate of 2- 3oz per square yard before planting.

Summer Varieties

The seeds of summer Cauli's such as 'snowball' can be sown in a heated propagator or on a windowsill from early January to March. Plant out under cloches until danger of frost is over. They will be ready to harvest in May or June.

All Year Round Varieties

These varieties are a little slower to mature, but sown and planted the same as the previous summer varieties they will be ready for harvesting from June to July.

By sowing and planting these two varieties a succession of cropping can be had until September.

Autumn Varieties

Sow in March or April in seedbeds. Transplant to the final positions when they are 3" high. Space out 2' apart. They will be ready for cutting from September to December.

Winter/spring Varieties

The seeds of these are originally Australian and take a lot longer to mature. Sow in seedbeds in April and May and transplant when 3" high to permanent positions. Space out 2'6" apart. The heads will be ready for harvesting from late autumn to late winter.

General sowing of all varieties

Sow the seed thinly in a shallow seed drill, thin to 6". Transplant to the final growing positions when they are 3" high and space them out accordingly.

One problem that is common to Cauliflowers is that some seedlings tend to come up 'blind'. This means that the tiny central bud that eventually forms the head does not form. When transplanting each plant should be inspected to make sure that the bud is there. Discard any 'blind' plants, as they are useless.

Another problem with Cauliflowers is that they do not take too kindly to having their roots disturbed or having any sort of check put on their growth pattern. Plants that have been checked in some way will have a habit of not growing and then trying to produce a head. This causes small button size heads to form on very small plants, which subsequently prove to be useless. This problem is known as 'premature curding'.

For this reason Seedlings should be kept well watered and transplanted while no more than 3" high. Disturb the root ball as little as possible and, if any pest or disease problems are encountered they should be dealt with promptly to avoid a check to the plant.

If Clubroot tends to be a problem, the seeds can also be sown in pots or trays in the greenhouse or coldframe and when the seedlings have formed two leaves transplant to 3" cell trays. Grow on until they are 2 ½" - 3" inches tall and then transplant them to the final positions. This gives the plant chance to get a good root system before being exposed to the virus. Use one of the commercial Clubroot dips when planting out.

It is also a good idea to treat the ground when planting with a soil pest killer such as Chlorophos as a prevention against Cabbage root fly.

As the heads develop, bend the outer leaves over the head to keep the curds white Harvest the heads as required, depending upon the variety. Remove any yellowing or dead leaves as you pick.

A shortage of Molybdenum may result in a condition know as 'whiptail', this makes the leaves thin and deformed. Boron deficiency causes the small and bitter curds and the leaves to turn brown. A shortage of Magnesium turns the leaves yellow, reddish brown or purple. The correct soil management can avoid all these.

Cauliflowers are subject to all the usual Brassica pests and diseases such as Club root, Cabbage root fly, Cabbage White caterpillars, Mildew and whitefly. (See relevant Pests or Diseases section).