When to Plant Basil in Brisbane, Subtropical Guide

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

This Basil 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.

Basil

Photo: Wikimedia Commons

The king of summer herbs. Sweet basil (O. basilicum) is the standard culinary variety, but Thai basil (O. basilicum var. thyrsiflora), lemon basil (O. x citriodorum), and purple basil (O. basilicum 'Purpurascens') each bring distinct flavours. Extremely frost-sensitive. Even a light frost kills it dead. Thrives in warm conditions across most of Australia from spring through autumn.

Planting Calendar for Subtropical

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

S = Seed Tray   T = Transplant   D = Direct Sow

Want a nudge when it is Basil sowing time in Brisbane?

One email a week with what is worth planting in the Subtropical zone right now, Basil 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: 20.4°C (optimal range: 18–35°C) ✓ Ready to plant

That figure is read off my own weather station here at Dayboro in South East Queensland at 18:55 yesterday, not a model. The radar, the rain gauge and the forecasts behind it sit on Dayboro.au.

How to Grow Basil in Subtropical Australia

When to Plant

Seed trays Aug-Feb. Transplant Sep-Mar. Peak season Oct-Mar. Dead by May from cool nights.

Soil
Rich, well-drained soil with plenty of compost. Warm soil is critical.
pH Range
6.0-7.0
Sunlight
Full sun (minimum 6 hours). More sun = more essential oils = more flavour.
Spacing
25cm apart, 40cm between rows
Watering
Regular, consistent watering. Basil wilts dramatically when dry but recovers quickly. Water at base, not overhead, to reduce fungal issues. Morning watering preferred.

Companion plants: Tomato, Capsicum, Chilli, Marigold

Avoid planting near: Rue, Sage, Common Thyme

Subtropical Growing Tips for Basil

Recommended Varieties

  • Genovese (standard sweet basil)
  • Thai basil
  • Lemon basil
  • Purple basil
  • Tulsi

Key Challenges

  • Short season if spring is cool
  • Downy mildew in humid spells
  • First autumn cold snap kills plants

Pro Tips

  • Start seeds indoors in August for earliest harvest
  • Pinch flower buds relentlessly for longer harvest
  • Take cuttings in February to root for autumn pot plants indoors

Harvesting Basil

When ready: Begin harvesting when plants have 6+ sets of leaves. Harvest before or at first sign of flower buds for best flavour.

How to harvest: Pinch or cut stems just above a leaf pair. This encourages two new shoots from that node. Never strip more than 1/3 of plant at once. Harvest in morning after dew dries when essential oil concentration peaks.

Common Basil Pests in Subtropical Zones

Aphids and Fungal Issues, risk: LOW (score: 36/100)

Organic prevention: Avoid excess nitrogen. Companion plant with marigolds. Check plants regularly.

View all pest alerts →

Where to next

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

Also worth sowing in the subtropical zone this September: Lemongrass, Ginger, Beetroot and Chilli Peppers.

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Common Questions About Basil

When do you plant basil in Australia?

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

Does basil grow all year round in Brisbane?

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

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.