about

Cauliflower is a “cole” crop in the Brassicaceae family, which includes broccoli, collards, and cabbage. Cauliflower came from the Mediterranean region, and dates back at least two thousand years. It is grown for its edible head, or ‘Curd’, which is an underdeveloped flower stem and buds.

The ‘curd-like’ variety of cauliflower typically consumed in the United States is often compared to broccoli, with dense, fused, white, florets connected by a thick stem and surrounded by leaves. There are also ‘loose curd’ varieties of cauliflower which are popular in many different cultures, and look like broccoli raab, with long stems and a flowery type of head. Cauliflower is usually white but can come in many different colors including green, yellow, orange, and purple. Despite the changes in color, cauliflower always tastes the same with a mild and slightly nutty flavor. Popular varieties are Amazing, Waltham, Romanesca and Rober.

Cauliflower is a cool season biennial grown as an annual plant that reproduces by seed. In North Central Florida it grows in the cooler months from October to March. It takes two to three months for cauliflower to reach maturity, depending on if it was direct seeded or transplanted and makes a great addition to your cool-season garden.

Cauliflower may be grown from seed or from transplants purchased at garden centers. It grows best in full sun with well-drained, fertile soil, with a pH between 6.0 and 7.0. To increase the organic matter in your soil, mix aged manure and/or compost into the bed before planting.

If directly seeding into the garden, seeds should be planted at a depth of 0.25 to 0.5 inches. From seed, it takes 75 to 90 days for cauliflower to reach maturity.

You can also start seeds in trays indoors 6 weeks before desired planting date. The seeds are very small and can be shallow planted in flats of germination mix. Temperatures of about 70º to 80ºF are optimum for germination. Seedlings can then be transplanted individually 4 to 6 weeks later. Before transplanting to the garden harden off seedlings by gradually exposing them to the outdoor environment 2 weeks before planting. The transplants will be ready for planting when they have 4 to 5 leaves.

Cauliflower is more commonly purchased as transplants in 4 or 6 packs.  The transplants should be planted 15 to 18 inches apart in good, well composted garden soil or in raised beds. Transplants will take 50 to 70 days to reach maturity. Unless a large quantity of cauliflower is needed transplants can be moved one at a time from the pack into the garden every 7 to10 days to prolong the harvest season.

Recommended cultivars for Florida include:

• Alcala: good heat tolerance with round and dense heads

• Bermeo: early maturing and heat tolerant with uniform medium sized heads

• Flamenco: excellent flavor and raw eating quality with bright white, domed heads

Water availability is important for the success of cauliflower. After direct seeding, water every three days to establish seedlings. Once seedlings are established, or after transplanting, water consistently and do not let the soil dry out. Mulching is suggested, as it helps to conserve soil moisture. The most important period for watering your cauliflower is during head development. And during times of high temperature, watering can help to cool off the plants. Suggested methods of watering include sprinklers, drip, and hand-watering.

Cauliflower has a high requirement for nutrients, either from soil organic matter or fertilizers and nitrogen is important for this crop to produce a high-quality product. For the best growth of your cauliflower, use a starter fertilizer or manure when transplanting, and side-dress half-way through the growing season and as needed. Keep the bed free of weeds to avoid competition for nutrients and take care not to disturb the plant’s roots.

Very high and low temperatures can cause stress to cauliflower plants. Extreme cold temperatures can halt growth or cause buttoning (premature head development). Leaves can be damaged by frost, so protection such as frost covers may be needed in the coldest months. Warm weather can delay maturity and may cause plants to bolt or develop leaves among the heads. If temperatures are high, shading can help cool the plants. Symptoms of stress in cauliflower can be seen in the coloring of the head. For white varieties of cauliflower, pink heads indicate too much sun exposure or temperature fluctuations.

Cauliflower can be attacked by insects like those that attack broccoli and cabbage. This includes cutworms, cabbage worms, and cabbage loopers. These pests can be controlled by spraying with Bt, handpicking, or fine mesh row covers. Aphids are also a potential pest for cauliflower and can be controlled using insecticidal soaps or strong streams of water. Cauliflower is susceptible to root rots, which has a symptom of yellowing leaves. To control diseases, keep your garden free of debris, remove and destroy infested plants, and do not handle plants when they have just been watered. Cauliflower should not be planted in the same bed where it or other brassica has been grown for the past two to three years.

Cauliflower is ready to harvest when the heads are firm, compact, and reach 6 to 8 inches in diameter. This occurs 55 to 100 days after transplanting, or 85 to 130 days after direct seeding, and in general about 1 to 2 weeks after blanching begins. Harvest the whole head by cutting the stem with a sharp knife, leaving some leaves around the head to keep it protected. The leaves can also be harvested and cooked like collards or cabbage. If the heads remain small, but have started to open, you can harvest since they will most likely not mature. Heads that are coarse or grainy in texture are past maturity.

Direct sunlight on uncovered cauliflower heads can cause some varieties to turn yellow, brown, or blotchy purple. To keep them white, cauliflower heads need to be sheltered or covered in a process called “blanching”. When the head is 2 to 3 inches in diameter, the longest leaves above the head are gathered and then tied together to keep light out. Check the cauliflower weekly for pests and untie after rain to let the head dry out. If the weather is warm during the blanching period, tie the leaves loosely to allow air circulation. Some varieties of cauliflower are self-blanching, with leaves that wrap around the head of the plant and protect it from the sun.