Organic feed helps grow bumper caulis
Cauliflowers are fickle plants. Of all the brassicas, they’re the trickiest to grow. They may produce a head, they may not. It depends, to some degree, on the weather – and how good you are at watering. These edible flowers are sensitive to hot and cold at certain stages of growth. If temperatures are extreme they’re unlikely to produce a head. If frosts occur while plants are still in the seedling stage, they may not survive. Late summer/early autumn and spring are the best times to plant cauliflowers. But they need to grow quickly. If growth is checked (not enough food or water to keep them growing, for example) heads may be small, or they won’t form at all. A month or so ago I picked the biggest cauliflower heads I’ve ever grown. I watered them every day and fed them with an organic fertiliser. I used Kiwicare’s Nourish All-Purpose Organic Fertiliser, which containers a mix of seaweed, fishmeal, natural salts, and environmentally friendly microflora. Seaweed may have been the key to healthy growth. Besides nitrogen, phosphorus and potassium, seaweed contains many micronutrients, including boron and molybdenum. Both of these are ideal for cauliflower growth, as a boron deficiency may cause cauliflowers to become stunted and have hollow stems, a molybdenum deficiency may result in whiptail, where the growing point becomes deformed and the leaves are narrow and twisted. A molybdenum deficiency is much more likely in sandy soils or soils with a pH of less than 5.8, as the trace element becomes less available in acidic soils. Liming the soil will help in the long run. However, in over-limed soils, boron and manganese becomes less available. Liming is also used to reduce the incidence of club root, a fungal disease that attacks the roots of brassicas. The roots become swollen and ‘‘clubbed’’, forming galls, resulting in an inability to take up water and nutrients. Plants consequently grow poorly and wilt. Club root likes wet soils and is more severe in acidic soils, so adding lime is beneficial. Cauliflower seeds may be sown directly in the ground or planted in small pots for transplanting when seedlings are 10cm to 12cm high. Plant only a few of one variety at a time because your cauliflowers will reach maturity around the same time. Plant in rich, well composted soil in full sun. Water regularly to encourage quick growth and feed with a balanced fertiliser that contains trace elements too. Plants can take between 12 and 28 weeks to mature, depending on the variety. Cauliflower ‘‘All Year Round’’ matures in about three months. ‘‘Snowmarch’’ on the other hand can take seven months to mature. As the cauliflowers start to develop, snap the centre vein in long outer leaves and fold them over the heads to keep the sunlight from discolouring them. Harvest the heads before they start to loosen up.