They are not the easiest vegetable to grow which puts many off the idea of even attempting to try this wonderful tasty crop. The soil must be healthy; it demands that the soil is sweet, with a pH range of 6.5 – 7.5, deeply dug with a very high fertility level. Anything that slows down the growth, such as insects, lack of water, excessive heat or cold, may prevent the development of the head.
Sandy loam is preferable with enrichment of well-rotted manure and compost at a rate of one bucketful to the sq. yd. It is an advantage if cauliflowers follow a well-manured crop like potatoes or peas; doing this the ground will be firmer and in good condition. If the soil is not already chalky or limy after the initial soil preparation, apply carbonate of lime as a top dressing at the rate of 5 oz. (150g) to the sq.yd.
About ten days before planting, apply a fertilizer such as fish manure, bonemeal at the rate of 3 oz. (90g) to the sq. yd. You may also add some wood ash or sulphate of potash at 1 oz. (30g) to the sq. yd.
Make the first sowing in January, keeping them on staging in a greenhouse at a temperature of 50 deg. F. (10 deg C.). When the seedlings come through, prick out and replant into pots containing similar soil. At the beginning of March put the pots out into a frame to harden the plants off; let them get acclimatised to the outside atmosphere until the end of March, then transplant them into the bed where they are to mature.
Make the second sowing in late April thinly into moist, firm soil, in frames, which should be as similar to John Innes compost as possible. Keep the frame closed until germination takes place then allow a little ventilation on mild days. When the seedlings come through, prick out and replant into pots containing similar soil; these will be ready to plant out in June.
The third sowing is made in May, in the seedbed in a sunny, sheltered position. Make drills about ½ in. (12mm) deep and sow the seeds thinly. After covering the seeds make sure that the soil is firmed over with the head of a rake. It is important to remember that whenever cauliflowers are transplanted they must be planted shallowly. If the base of the leaves are buried it will deform the plant and they will not develop the centres.
During the growing period, many old gardeners would give their cauliflowers a dressing of soot, but in this modern era of gas, electric, and for that matter solar-powered heating, it is unlikely that this substance is available to the majority of today’s gardeners. Instead, dried blood at a rate of 2 oz. (60g) to the sq. yd. can be given.
Always cut the cauliflowers early in the morning whilst the curds are moist with dew. If a number of curds appear to be ready at the same time and they are not all required at once, break the midribs of two or three of the centre leaves on each plant that is not needed so that they cover the curd-like an umbrella and protect it for a few days until they are required. The cauliflower will keep however for about three weeks if it is pulled up, including roots, and hung upside down in a dry shed.