Grow your own Cauliflower

March 31, 2025

There’s something deeply satisfying about harvesting a big, beautiful homegrown cauliflower and taking it straight to the kitchen to show it off to the family! Some say they are tricky to grow… but with the right timing, good soil, generous feeding and a little TLC, you’ll be harvesting super-sized cauliflower heads like a pro!

When to Plant

Cauliflowers love cool weather— they typically take 3-4 months to grow so plant early enough so they mature before summer heat kicks in!
In temperate to subtropical areas, plant seedlings from March to June.
In the tropics, wait until April–May for best results.
In cold climates, plant by February/March and again in spring.

Soil Prep & Planting

Prepare the soil well:
- Add plenty of compost or aged manure a week before planting.
- Sprinkle a handful of organic fertiliser per square metre for extra nutrients.
- Check the pH. A reading of 6.5–7 is ideal – if it’s below this, add lime to sweeten the soil. (You can buy simple inexpensive pH testing kits at your garden centre).
Pick strong seedlings for planting out.
Cauliflowers get big! Space plants 45cm apart in rows 60cm apart.

Water, Feed & Care

Keep soil consistently moist—dry spells lead to small, bitter heads.
Feed lightly but often:
- A light sprinkle of organic fertiliser every 4-6 weeks.
- Fortnightly liquid feeds of seaweed extract and fish emulsion.
Check for pests! Pick off caterpillars by hand or spray with Dipel (Bt) or natural pyrethrum if needed. A great way to keep pests at bay is to cover your cauliflower plants with fine weave pest exclusion netting, available at your garden centre.
Mulch well: Maintaining a 5-7cm layer of sugarcane mulch locks in moisture and reduces weeds.

Growing in Pots

If you’re short on space, you can grow cauliflower in large pots.

Choose a pot at least 30cm wide and deep for one plant. A 40cm pot can hold three compact varieties (see ‘Best Cauliflower Varieties to Try’).
Use Pot Perfection Blend in compost and coir peat to retain moisture. Add a sprinkle of organic fertiliser for extra nutrients.
Place in full sun: More sun = bigger, better heads!
Water & feed: Keep soil moist but not soggy, and feed weekly with liquid fertiliser.

Protecting the Curds (Heads)

Too much exposure to sun can cause your lovely white cauliflower heads to turn yellow. When the curds reach tennis ball size, fold outer leaves over to cover and protect the head and tie loosely with twine.
Frosty weather? Cover heads with a light cloth overnight to prevent damage.

Harvesting

Most cauliflower varieties take 3-4 months to mature.
Pick when the head is full, firm, and tightly packed—don’t wait too long, or the florets will start to separate!
Use a sharp knife to cut the head cleanly from the plant.
When storing cauliflower in the fridge, wrap the whole head in a perforated plastic bag, and put it in the crisper. It will keep for a week or so.