This species has been cultivated as a food crop for many hundreds of years and, in that time, several quite distinct forms have arisen. The nomenclature of these forms is confused, to say the least, and by no means universally accepted. We have followed the treatment used by GRIN, though it is very likely to be revised in the future[].

Common Name: Cauliflower

General Information

Cauliflower is a biennial plant derived in cultivation from the wild cabbage. It has a shallow root system, from which grows a short thick, usually unbranched stem with a rosette of leaves, producing a large head of abortive flowers on thick hypertrophied branches (the edible cauliflower) at the top of the stem.
Cauliflower is a widely cultivated food crop, grown mainly in the temperate zone, for its edible immature flower heads (or curd).

Known Hazards

None known

Botanical References

Range

A cultivated form of Brassica oleracea

Habitat

Not known in the wild.

Properties

Edibility Rating
Habit	Biennial
Height	0.75 m
Pollinators	Bees
Self-fertile	Yes
Cultivation Status	Wild

Cultivation Details

The cauliflower has been derived through cultivation in milder regions of the temperate zone, and can also be grown in the tropics, especially at higher elevations. It grows best in areas where annual daytime temperatures are within the range 10 - 25°c, but can tolerate 5 - 30°c[]. When dormant, the plant can survive temperatures down to about -5°c, but the curds can be severely damaged at -2°c[, ]. It prefers a mean annual rainfall in the range 600 - 1,100mm, but tolerates 450 - 1,900mm[].
Succeeds in full sun in a well-drained moisture-retentive fertile soil with plenty of lime[, , ]. Cauliflowers, especially the winter and spring maturing types, should not be given a soil that is too rich in nitrogen since this can encourage soft, sappy growth that is more susceptible to winter cold damage[]. Prefers a heavy soil[]. Requires a warm sunny position[]. Prefers a pH in the range 6 to 7[], though it tolerates a pH in the range 5.5 - 8.5. Succeeds in maritime gardens[]. Lack of moisture in the growing season can cause the plant to produce small or deformed curds[].
Yields from 12 - 25 tonnes per hectare can be obtained[].
There are many named varieties and, by careful selection, it is possible to provide cauliflowers all year round. The summer and autumn maturing cultivars are annuals, they need to produce a certain number of leaves before curd development will be initiated. The optimum temperature for this is around 17°c, but at temperatures above 20°c the curds will either be of poor quality or not be produced at all[]. Winter and spring maturing forms are biennial and need exposure to temperatures below 10°c before they will produce curds and once again, this will not happen unless the plant has reached a certain size[].
Summer varieties are not very cold hardy and will be damaged by light frosts, winter varietes are more hardy and will tolerate temperatures down to about -6°c, though the curds are more sensitive and can suffer damage at about -2°c[]. This damage can often be prevented by bending over the leaves so that they cover the curd[].
Cauliflowers are widely grown for their edible immature flower heads (or curd).

Edible Uses

Immature flowering head - raw or cooked[, , , ]. A mild cabbage-like flavour, they make an excellent cooked vegetable and are also very acceptable in salads[]. By careful selection of cultivars, it is possible to produce flowering heads all year round[].

Leaves - cooked[]. A mild cabbage flavour, they make a good cooked vegetable[]. Do not over-harvest them, however, since this would adversely affect the production of the flowering head[].

Medicinal

None known

Agroforestry Uses:

Grows well with celery and other aromatic plants since these seem to deter insect predations[, , ]. Grows badly with beet, tomatoes, onions and strawberries[, ].

Other Uses

An extract of the seeds inactivates the bacteria that causes black rot[, ].

Propagation

Seed - sow in a seedbed outdoors in mid spring to early summer depending on the cultivar. Plant out into their permanent position when the plants are 5 - 10cm tall. Seed of some cultivars can be sown in late winter in a greenhouse in order to obtain a harvest in early summer. Do not let the seedlings get overcrowded or they will soon become leggy and will not make such good plants. If your seedlings do get leggy, it is possible to plant them rather deeper into the soil - the buried stems will soon form roots and the plant will be better supported.