Last Updated on February 19, 2024 by Jason Nguyen
The oldest record of cauliflower dates back to the sixth century BCE. A member of the cabbage family, the word “cauliflower” comes from the Latin caulis, meaning “cabbage”, and floris, meaning “flower”. They are grown for their thick, undeveloped flowers and flower stalks, not for their leaves.
Of all the brassicas, cauliflower is the most difficult to grow, which is why it tends to be more expensive at the greengrocer. Aim for at least six hours of full sun each day for your cauliflower — though the more the better, really.
Cauliflower Label
Common name: Cauliflower
Botanical name: Brassica oleraceae var. botrytis
Family: Brassicaceae
Aspect and soil: Sun; deep, welldrained soil
Best climate: All, but grow in the cooler part of the year
Habit: Biennial vegetable grown as an annual
Propagation: Seed, seedling
Difficulty: Difficult
PROPAGATION
Prepare the patch by digging organic matter through the soil, which should be rich, moist and freely draining with a pH of 6–6.5 (the yield will be reduced if the soil pH is below 6).
Grow cauliflower from seedlings bought at your local nursery if you have a small vegie patch, as the plants need a lot of space. If you want to grow your own from seed, sow the seeds in seedling trays at the start of summer for transplanting into the patch six weeks later.
WATERING
Because cauliflower is a winter crop, most of the irrigation will be supplied by Mother Nature. However, if dry weather occurs, water every 10 days and apply enough to thoroughly wet the root zone.
Keep the soil moist but not soaked. Cauliflower plants must never be water stressed, especially as young plants, or they will bolt to seed and not form a dense flower.
MULCHING
Mulch helps soil retain moisture, controls weeds and regulates soil temperatures. If you choose not to mulch, you will have to
hoe the weeds. Cauliflowers have shallow roots, so be careful not to damage the roots if you do.
FEEDING
Cauliflowers do best in very fertile soil. Work the soil with well-rotted animal manure or compost before planting. Once the plants are growing well, apply seaweed extract every couple of weeks.
BLANCHING
When the cauliflower head can be easily seen, it is ready to blanch. This process prevents sunlight from reaching the head, keeping it nice and white rather than letting it become a yellowish green.
Tie or peg the outer leaves over the head to protect it from the sunlight. The head should be ready to harvest a couple of weeks after blanching.
PRUNING
As the plant grows, remove any old leaves that have started to turn yellow and put them in the compost.
POLLINATION
Cauliflower requires cross-pollination if you want to save seeds. Its small yellow flowers are pollinated by insects
PESTS AND PROBLEMS
Caterpillars are notorious pests on brassicas and cabbage white moths are the main offenders. Look out for caterpillars on the leaves, or the holes and droppings they leave behind.
Slugs can be a problem, chewing through seedlings and mature plant leaves alike, particularly during wet seasons, and aphids also cause havoc for brassica crops. Try planting marigolds, or other plants from the Tagetes genus, among the crop as a repellent.
HARVESTING AND STORAGE
Start harvesting when the heads are firm; once the florets start to separate, it is too late, though they are still edible.
Cauliflower heads can be stored in the fridge for two weeks or more.
HOW TO CONTROL CATERPILLARS
Pick the caterpillars off the plants (it’s worth wearing gloves if you don’t know what type of caterpillar it is) and drown them in a bucket of soapy water; or if you have chickens, provide them as an after-dinner snack — the chooks will love you for it. Caterpillars are soft-bodied and therefore a favorite treat for birds and small mammals.
Use a product called Bt, or Bacillus thuringiensis. Bt is also referred to as Dipel. It is an organic insecticidal bacterium that kills only caterpillars and is safe to use on edibles. It takes about 24 hours to have an effect but works a treat.
Use a garlic or soap spray.
Barbarea vulgaris, also known as winter cress, and Barbarea verna, or land cress, both contain a natural chemical called glucosinolate that acts as a toxin. Apparently the white cabbage moth will go crazy for it and lay its eggs all over it. When the young caterpillars hatch and eat it they will keel over.
I think the best organic method of control is covering the patch or crops of susceptible vegies with very fine netting. This stops the butterflies and moths from landing on the plants to lay their eggs. The downside is that the netting can limit access for other insects, which is a problem if there are plants in the patch that require pollination. If this is the case you can hand-pollinate.