How to grow Cauliflower in Australia
Cauliflower is the most demanding of the cabbage family, but a firm, white home-grown head is worth it. It needs firm, rich soil, cool weather while the head (curd) forms, and a steady supply of water and food from start to finish. Any check in growth, from dry soil to a late transplant, can leave you with tiny, buttoned heads.
📖 Our full guide: How to Grow Cauliflower in Australia
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| South East Queensland | February to April | |
| Northern Rivers NSW | February to May | Longer winter window than SEQ. |
| Sydney & Coastal NSW | February to May | Cool winters allow later plantings (May) for winter harvest. |
| Melbourne & Victoria | February to June | Seed indoors Feb to Mar (early), transplant Apr to May. Melbourne's long cool season extends harvest. |
| Adelaide & SA | December to March | Sow Dec to Mar so heads mature in cool weather. Winter or spring sowings run into November heat and button. |
| Perth & WA | February to August | Trays Feb to Mar in bright shade give the steadiest curds; transplant Mar to May. Quick self blanching types can still be sown to August. |
| Tasmania | November to January | Sow Nov to Jan, transplant by Feb to Mar, harvest through winter. Needs the long cool run that Tasmania provides. |
| Canberra & ACT | November to January | Sow Nov to Jan, transplant Jan to Mar so heads form in cool autumn. Later sowings stall in winter cold. |
| North Queensland | May and June | Dry season only. Most difficult brassica in tropics; sow May to Jun with heavy shade cloth. |
| Darwin & Top End | May and June | Dry season only. Most difficult brassica in tropics; sow May to Jun with heavy shade cloth. |
Where to plant
Grow cauliflower in full sun in firm, rich, well-drained soil with plenty of compost dug in a few weeks ahead. Lime acid soil, which helps prevent clubroot and makes the trace element molybdenum more available. Loose, freshly dug soil and anything that stresses the plant lead to small, uneven heads. Do not plant where cabbage family crops grew recently.
Time it so the heads form in cool autumn and winter weather. Heads that form in heat, or plants checked by cold as seedlings, often button.
- South East Queensland, the Northern Rivers and Sydney: sow from February to April or May.
- Melbourne: sow seed indoors in February and March and transplant in April and May.
- Adelaide: sow from December to March so heads mature in cool weather; winter or spring sowings run into November heat and button.
- Perth: sow trays in February and March in bright shade and transplant from March to May.
- Hobart and Canberra: sow from November to January and transplant by February or March, so heads form in the cool autumn.
- North Queensland and Darwin: the most difficult brassica in the tropics; try a May to June sowing with heavy shade cloth.
Choosing a variety
- Quick, early varieties suit warmer areas and short seasons. Slow, late varieties give big winter heads in cool climates.
- Self-blanching types have inner leaves that curl over the head, so they need less covering.
- Coloured cauliflowers (purple, orange and green) are also available and need no blanching.
How to plant
- Sow seed about 1 cm deep in punnets and keep moist.
- Plant out young, at four to five weeks old, before the seedlings get root bound. Late or rough transplanting is a common cause of buttoning.
- Space plants 50 to 60 cm apart and firm the soil well around each one.
- Water in, mulch, and cover with fine insect netting straight away.
Watering and feeding
Keep the soil evenly moist from planting to harvest; cauliflower does not forgive dry spells. Water deeply and mulch well.
Feed regularly with a nitrogen-rich liquid fertiliser every two to three weeks. Seaweed solution supplies trace elements; in acid soil, liming helps prevent molybdenum deficiency (whiptail), and a boron deficiency shows as hollow stems and brown, discoloured curds.
Pruning and care through the year
- Keep netting on until harvest.
- When a small white curd appears, fold a few of the large outer leaves over it and tie them loosely. This shades the curd from sun and frost, which turn it yellow or brown.
- Check under the netting and leaves for caterpillars.
Harvesting
Cut the head while the curd is still firm, tight and smooth, before the florets begin to separate or turn grainy. Check covered heads every few days once they start forming, as they can go past their best quickly in warm weather. Cut the stem below the head, keeping a few leaves around it for protection.
Cauliflower keeps a week or so in the fridge, and blanched florets freeze well.
Companion planting
Aromatic herbs and flowers that bring in helpful insects suit the cabbage family. Keep crops with different needs, and other brassicas, out of the same bed.
Good companions
- Dill Its flowers feed tiny parasitic wasps and hoverflies that attack caterpillars and aphids.
- Chamomile A low flowering herb that brings in hoverflies.
- Celery Shares the same cool season and rich, moist soil.
- Onion Narrow plants that fit between cauliflowers without competing for space.
- Beetroot A root crop that uses different space in the bed.
- Rosemary An aromatic herb traditionally grown near brassicas; plant it at the bed edge.
- Sage Another aromatic herb traditionally grown near brassicas.
Keep apart
Avoid planting these close to cauliflower.
- Strawberry Traditionally kept away from the cabbage family.
- Tomato A warm-season crop with different timing and feeding needs.
- Climbing beans Tall summer climbers that shade low winter crops.
Pests and diseases
Caterpillars are the main pest, and a single grub in the curd spoils it. Netting from planting is the most reliable control.
Pests to watch for
- Cabbage moth Holes chewed in leaves and green caterpillars or droppings in the curd, from cabbage white butterfly, cabbage moth and diamondback moth. Net plants.
- Aphids Grey, waxy colonies under leaves and in the curd.
Diseases to watch for
Common questions
Why is my cauliflower head so small?
Small, early heads, called buttoning, come from a check in growth: seedlings left too long in the punnet, rough transplanting, loose soil, dry spells, too little food, or cold or heat at the wrong time. Plant young seedlings into firm, rich soil and keep water and food steady.
Do I need to cover cauliflower heads?
For white cauliflower, yes. Once a small curd appears, fold a few outer leaves over it and tie them loosely. This keeps sun and frost off the curd, which can turn it yellow or brown. Self-blanching and coloured types need little or none.
When is cauliflower ready to pick?
When the head is firm, tight and smooth, before the florets start to separate. Check every few days, especially in warm weather.
When should I plant cauliflower?
Time it so the heads form in cool weather: from summer to autumn in most areas, and from late spring to early summer in Hobart and Canberra. Pick your region at the top of the page for the months.
Why is my cauliflower turning purple or yellow?
A white curd turns yellow or brown in sun and can take on a purple tinge in cold or stressful weather. Folding the leaves over the head prevents most of it. The curd is still edible.
How long does cauliflower take to grow?
Usually about 14 to 20 weeks from sowing, depending on the variety. Quick varieties are ready sooner, while large winter types take longer.
Sources we checked: University of Minnesota Extension: Growing cauliflower in home gardens; RHS: How to grow cauliflower; NSW DPI: Molybdenum deficiency in plants; RHS: Nutrient deficiencies; Gardening Australia: Bountiful Brassicas.