Herbs That Survive an Australian Summer (and the Ones That Never Will)

Pots of rosemary, basil and parsley herbs on a sunny Australian patio

Every November, a wave of herb-related guilt sweeps the country: the coriander has bolted, the parsley looks betrayed, and the basil is deciding hourly whether to live. Most of it isn’t your fault — it’s a mismatch between herbs bred for gentler summers and the actual thing that arrives here in January. The fix is knowing which herbs are genuinely heat-proof, which need managing, and which to simply stop planting in October. (Starting a whole first garden, not just herbs? The beginner vegetable list runs on the same honesty.)

The heat-proof brigade (plant with confidence)

The Mediterranean woody herbs treat an Australian summer as a homecoming: rosemary, thyme, oregano, sage (afternoon shade helps sage in the subtropics), and bay. Give them sun and drainage, skip the rich soil and heavy watering — soft treatment kills more of these than heat ever will. Alongside them, the tough non-Mediterraneans: chives (may nap in extreme heat, returns), lemongrass (subtropical royalty), mint — indestructible if watered, always in its own pot before it annexes the garden — and perennial basils, which shrug through heat that stops the annual kind.

The manageable middle

Sweet basil loves warmth but sulks past the mid-30s and hates drying out: morning sun, generous pots (size rules), consistent water, and constant tip-picking before flower spikes form. Once it flowers hard, flavour fades — succession-plant a second pot in December rather than nursing the first all summer. Parsley survives with afternoon shade and moisture, though summer parsley is never spring parsley; expect functional, not lush. Sowing anything in a heatwave is a waste of seed — wait for the break, or start punnets in shade.

The never-wills (stop blaming yourself)

Coriander is the big one. It’s a cool-season annual: heat and long days flip its switch from leaves to flowers, and no watering schedule reverses biology. In most of Australia, coriander is an autumn-to-spring crop, full stop (the calendar has the windows). Summer plantings bolt within weeks regardless of care. Similar story for dill and chervil — cool-season characters that treat January as a fire drill.

The summer swaps

This is where the subtropics stop being the problem and start being the advantage — swap the strugglers for their hot-climate stand-ins:

  • Perennial coriander (sawtooth coriander / culantro): stronger, coriander-adjacent flavour from a plant that likes humid heat. The classic Queensland answer to bolting.
  • Thai basil: holds structure and flavour through heat that flattens sweet basil; correct in half your summer cooking anyway.
  • Vietnamese mint (laksa leaf): thrives in warm wet conditions; another humid-summer specialist.
  • Society garlic and garlic chives: onion-family flavour that ignores the weather.

Getting everything through a heatwave week

Whatever the herb, the difference between “stressed” and “dead” in a 40-degree run comes down to a few moves: water deeply at dawn (method), mulch pots and beds, drag containers into afternoon shade — mobility is the whole point of pots — and don’t fertilise mid-heatwave (surge growth is exactly what fries). Full heatwave triage is its own guide in the works; for herbs, those four lines carry you.

The honest summary: match the herb list to the season instead of fighting it, and summer becomes rosemary-and-Thai-basil season rather than the season of guilt. Coriander will be waiting for you in April.

Related: Protecting Plants in a Heatwave: What Works in the Real 40-Degree Week.