When to Plant Sweet Corn in Brisbane, Subtropical Guide

Sow September to February. Right now in October you can sow.

Also called corn, maize.

Planting window
Sow direct in blocks from September to February. August soil is usually too cool, and March sowings meet the cold at cob fill.
Days to harvest
about 11 weeks
Sunlight
Full sun (minimum 8 hours). No shade tolerance.
Water needs
Deep water 2-3 times weekly. CRITICAL: increase at tasselling/silk stage. Water stress...
Spacing
30cm apart, 60cm between rows
Soil pH
5.8-7.0
Shop price
$11.76/kg average

This Sweet Corn guide is written for the Subtropical zone, which takes in Brisbane, the Gold Coast and the Sunshine Coast. Somewhere else? Your postcode picks the right one.

Not your zone? Cairns Sydney Melbourne Canberra Alice Springs Perth

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

Sweet Corn

Photo: Wikimedia Commons

Sweet corn is a warm-season grass requiring block planting for wind pollination. Freshly picked corn is dramatically sweeter than shop-bought because sugars convert to starch within hours of picking. Requires significant space (minimum 4x4 block) and cannot be grown as single plants or rows.

See what grows now in your own postcode

Planting Calendar for Subtropical

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

S = Seed Tray   T = Transplant   D = Direct Sow

Want a nudge when it is Sweet Corn sowing time in Brisbane?

One email a week with what is worth planting in the Subtropical zone right now, Sweet Corn 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: 21.6°C (optimal range: 16–35°C) ✓ Ready to plant

That figure is read off our own weather station in South East Queensland at 8:55 this morning, not a model.

What this month normally looks like

In October the Subtropical zone normally runs 27°C by day and 15°C overnight, with about 77 mm of rain over 7 wet days. The coldest October night on record across the zone was -0.2°C, so a late frost is not out of the question. Averages 1991 to 2026, 33 postcodes, SILO.

How to Grow Sweet Corn in Subtropical Australia

When to Plant

Sow direct in blocks from September to February. August soil is usually too cool, and March sowings meet the cold at cob fill.

Soil
Deep, fertile, well-drained soil enriched with compost and aged manure. Heavy feeder.
pH Range
5.8-7.0
Sunlight
Full sun (minimum 8 hours). No shade tolerance.
Spacing
30cm apart, 60cm between rows
Watering
Deep water 2-3 times weekly. CRITICAL: increase at tasselling/silk stage. Water stress causes bare cob patches.

Companion plants: Beans (Three Sisters), Pumpkin/Squash, Cucumber

Avoid planting near: Tomato (shared corn earworm)

Grow before, grow after

Sweet Corn belongs with the other fruiting crops, the fruiting crops turn of a four turn bed rotation.

Grow before it
Leafy greens and brassicas (Lettuce, Silverbeet, Broccoli)
Grow after it
Roots and alliums (Carrot, Beetroot, Onion)

Give the bed 3 turns before other fruiting crops go back in. Corn, okra and sunflower are heavy feeders that sit with the fruiting crops in the cycle.

Subtropical Growing Tips for Sweet Corn

Recommended Varieties

  • Honey and Cream
  • Golden Bantam
  • Balinese
  • Early Gem

Key Challenges

  • Corn earworm
  • Fall armyworm increasing
  • January heat stress on pollination

Pro Tips

  • Block plant 4x4 minimum
  • Three Sisters works excellently in SEQ
  • Bt on silks at first emergence

Harvesting Sweet Corn

When ready: Silks brown/dry. Cob full and firm through husk. Kernel exudes milky juice when pierced with thumbnail (milk stage).

How to harvest: Grasp cob, snap downward while twisting. Eat immediately. Sugar converts to starch within hours.

Preserving: pressure canning

6 tested pressure-canning recipes for Sweet Corn: 4 where it is the crop being canned and 2 where it is a main ingredient. Each one comes from published home canning guidelines. The conversion to Australian units is ours, with psi beside every kPa. Always follow your pressure canner's manual.

Recipes in this set

  • Corn
  • Corn: Cream Style
  • Sweetcorn, cream style
  • Sweetcorn, whole kernels
  • Succotash (sweetcorn and lima beans)
  • Mixed vegetables

The full recipe details are for members on a paid plan: jar sizes, headspace, process time, the pressure for a weighted or dial gauge at your altitude, the ingredients, the preparation steps and the safety notes.

See the plans

Worth growing?

A 2.4 m × 1.2 m bed fits 12 plants, about $35 worth at today’s Aldi, Coles, IGA and Woolworths prices, checked on 10 October.

That is roughly 3 kg at $11.76 a kilo.

Draw your sweet corn bed → No account needed.

Common Sweet Corn Pests in Subtropical Zones

Corn Earworm and Fungal Infections, risk: LOW (score: 26/100)

Organic prevention (Corn Earworm (Helicoverpa)): Remove old plants. Crop rotation.

View all pest alerts →

Where to next

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

Also worth sowing in the subtropical zone this October: Lemongrass, Beetroot, Cucumber and Dwarf Beans (Bush).

The pest most likely to find your sweet corn: Corn Earworm / Tomato Grub (Heliothis).

Supermarket Price

Current average retail: $11.76/kg (12-month range: $6.98–$16.25)

Grow your own and save on grocery bills.

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Common Questions About Sweet Corn

When do you plant sweet corn in Australia?

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

Does sweet corn grow all year round in Brisbane?

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

What else is sweet corn called?

Sweet corn is the usual Australian name. Overseas seed packets and recipes call it corn, maize. 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 Subtropical zone, Brisbane is its reference city.