When to Plant Zucchini in Cairns, Tropical Guide

Sow March to September. Right now in September you can sow.

Also called courgette.

This Zucchini guide is written for the Tropical zone, which takes in Cairns, Townsville and Darwin. Somewhere else? Your postcode picks the right one.

Not your zone? Brisbane Sydney Melbourne Canberra Alice Springs Perth

Also handy: will it frost this week? and what grows in shade.

Zucchini

Photo: Wikimedia Commons

Zucchini (courgette) is the quintessential productive home garden vegetable. A single plant can produce more fruit than a family can eat. A warm-season C. pepo cucurbit with bush habit, making it suitable for smaller gardens. Fast-growing, prolific, and forgiving. The classic 'too much zucchini' problem is real. Plant fewer than you think you need.

Planting Calendar for Tropical

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
- - S S/T/D S/T/D S/T/D S/T/D T/D T - - -

S = Seed Tray   T = Transplant   D = Direct Sow

Want a nudge when it is Zucchini sowing time in Cairns?

One email a week with what is worth planting in the Tropical zone right now, Zucchini included, plus which veg has jumped in price at the supermarket. Free, and you can stop it in one click.

Current Growing Conditions

Soil temperature: 21.4°C (optimal range: 18–35°C) ✓ Ready to plant

Modelled from Open-Meteo forecast (Cairns), not a live sensor.

How to Grow Zucchini in Tropical Australia

When to Plant

Year-round, dry season preferred. Wet season possible but heavy disease pressure.

Soil
Rich, well-drained soil with plenty of compost. Raised beds excellent.
pH Range
6.0-7.0
Sunlight
Full sun (minimum 6 hours daily)
Spacing
90cm apart, 120cm between rows
Watering
Deep water 2-3 times weekly at base. Avoid wetting leaves, powdery mildew magnet. Consistent moisture during fruiting.

Companion plants: Corn, Beans, Nasturtium, Marigold, Borage

Avoid planting near: Potato, Other C. pepo varieties if seed saving

Tropical Growing Tips for Zucchini

Recommended Varieties

  • Black Beauty
  • Blackjack
  • Greyzini
  • Gold Rush (yellow)

Key Challenges

  • Powdery mildew severe year-round
  • Pumpkin beetle
  • Whitefly
  • Virus pressure

Pro Tips

  • Fast crop: 45-50 days seed to harvest
  • Succession plant every 4-6 weeks for continuous supply
  • Milk spray weekly as preventative from day one

Harvesting Zucchini

When ready: 15-20cm long for standard varieties, 8-10cm for round types. Skin glossy and tender (can pierce with thumbnail). Firm but not hard.

How to harvest: Cut with sharp knife leaving 2-3cm stem. Pick YOUNG. Check plants DAILY in warm weather. A 15cm zucchini today is a 30cm marrow tomorrow.

Worth growing?

A 2.4 m × 1.2 m bed fits 3 plants, about $82 worth at today’s Aldi and Coles prices, checked today.

That is roughly 15 kg at $5.44 a kilo.

Draw your zucchini bed → No account needed.

Common Zucchini Pests in Tropical Zones

Squash Vine Borer, risk: MODERATE (score: 50/100)

Organic prevention: Crop rotation. Protect young plants.

View all pest alerts →

Where to next

What zucchini costs in the shops right now, retailer by retailer, updated daily.

Also worth sowing in the tropical zone this September: Lemongrass, Ginger, Cucumber and Basil.

The pest most likely to find your zucchini: Downy Mildew.

Supermarket Price

Current average retail: $5.44/kg (12-month range: $3.90–$7.98)

Grow your own and save on grocery bills.

Get the Full Interactive Guide

Track your garden, get real-time pest alerts, and plan around your zone's weather.

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Common Questions About Zucchini

When do you plant zucchini in Australia?

It depends on your climate zone, not the calendar month alone. Planting months by zone:

Does zucchini grow all year round in Cairns?

No. In the Tropical zone the planting months are Mar to Sep. Outside that window it either bolts, sulks or gets cut down by the weather.

What else is zucchini called?

Zucchini is the usual Australian name. Overseas seed packets and recipes call it courgette. Same plant, same growing advice.

Which zone am I in?

Type your postcode into the box under the heading and the page tells you, and links this crop in your own zone if it differs. Or look it up on the grow zone map. This page is the Tropical zone, Cairns is its reference city.