Sowing to harvest time: 18 to 24 weeks for summer and autumn varieties; 40 weeks for winter varieties.
Yield: 1 kg (21b) per plant.
Climate preferred: Cool temperate to subtropical.
Aspect: Open, but sheltered from cold winds.
Soil: Rich, fertile loam, but sandy soils are suitable if plenty of organic material has been incorporated during the winter. ‘Summer’ cauliflowers are in season from mid-summer to early autumn; ‘autumn’ varieties from mid-autumn to early winter and ‘winter’ cauliflowers from mid-winter to early spring. Consider growing one of the Australian varieties, which are dwarf growing and which produce superb little firm white heads in autumn.
Sowing and planting
Summer varieties should be sown indoors in mid-winter and set outside in mid-spring to provide a midsummer crop. Autumn varieties should be sown outdoors in mid- and late spring and trans-planted towards the end of early summer. Winter varieties should be sown outdoors in late spring and transplanted in midsummer. The seed should be sown 1.3 cm deep, and the seedlings are ready to transplant when they have six leaves.
Two weeks before transplanting give the soil a top dressing of general fertilizer at the rate of 135gm per sq m (4oz per sq yd). Set the plants in holes which have been previously filled with water and allowed to drain, 60 cm (2ft) apart each way. The little plants should sit at the same level as they did in the seed bed. The secret of success with cauliflowers is to keep them well watered. If you let them wilt during the first few days after transplanting, they are unlikely later to produce tight heads.
A top dressing of nitrochalk at the rate of 34 gm per sq m (1oz per sq yd) should be applied in rings around the plants at four weeks and again at eight weeks after setting them out to improve the quality and flavour of the curds. Summer varieties should have a few leaves bent over the curds to protect them from the sun and to keep them snowy white. With winter varieties a similar measure protects the curds from the yellowing effect of frost and snow.
Pests and diseases
Aphids, caterpillars, club root, flea beetles and root fly.
Cut cauliflowers while they are still small and tender. Summer and autumn varieties are at their best if cut in the morning with the dew still on the curds. In frosty weather, winter cauliflowers are best cut at midday. Cauliflowers hung upside down in a shed or garage remain in good condition for two weeks. Otherwise, store by freezing.
Cauliflower is not so generally useful as broccoli, as the season is shorter and the plants less hardy. The flavour is very delicate. It is almost impossible to give too much manure or compost. The situation should be sunny, but reasonably sheltered. Seed may be sown in boxes in a warm greenhouse in February or direct in a frame in March. Outdoor sowing cannot be attempted till early April, and then plants are usually too late to be of much use. Another plan is to sow outdoors in early September and transfer seedlings to a frame or cloche at the end of October, spacing them 3 in. apart each way. They are transplanted to the open ground the following April to crop in late summer.
Plants from late winter and early spring sowings should be hardened off in readiness for planting out in May or early June. Set them 2 ft. apart in rows 21 ft. apart. A week or so later give a sprinkling of nitrate of soda or Nitrotchalk at 1 oz. per square yard.
Reliable varieties are Pioneer, All the Year Round, Novo, Early White London, Snowball, Veitch’s Autumn Giant, and Walcheren.
Club root, cabbage caterpillars, cabbage root fly and flea beetle are the commonest foes.