15th August 2026

Born of Fire: How Smoke Wakes the Wildflowers

There is a paradox at the heart of the Western Australian bush, and it runs like this: some of our most breathtaking wildflower displays appear not despite fire, but because of it. Walk through country a year or two after a burn and you may find it more riotously alive with flowers than the untouched bush beside it, grass trees hoisting towering spikes, seedlings carpeting the ash, orchids emerging where none grew before. For a great many plants here, fire is not a catastrophe to be endured. It is a starting gun. Elsewhere in the world, fire is the disaster. Here, it is the invitation. And the story of how these plants learned to hear it is one of the finest pieces of science this state has ever produced.

The alarm clock hidden in the smoke

For decades, botanists knew that smoke did something peculiar to certain seeds. Countless Western Australian species would lie dormant in the soil, sometimes for years, stubbornly refusing to germinate, and then, in the season after a bushfire swept through, they would erupt into life all at once, in their thousands. The smoke, somehow, was the trigger. But nobody could say what, in that roiling, complex haze of a burning forest, the seeds were actually responding to. Smoke is a chaos of hundreds of compounds. Which one was the signal?

The answer came, in 2004, from a laboratory in Perth. A team of researchers at the University of Western Australia, working alongside Kings Park, finally isolated the active ingredient: a previously unknown molecule produced when plant matter burns and, it turned out, the first of a whole new family of compounds. These molecules are, in essence, a chemical wake-up call. Seeds detect them, read them as proof that fire has just swept the ground clear overhead, and germinate into the sunlit, competition-free, ash-fertilised opening the fire has kindly prepared. The seed has, in effect, been waiting underground for a message that says: the coast is clear, the soil is rich, go now.

And here is the detail that ought to be far better known than it is. The compounds were named karrikins, from karrik, a word for smoke in the Noongar language of the South West. A piece of cutting-edge global chemistry, named in honour of the people who have read and tended this fire-shaped country for tens of thousands of years. Smoke has since been shown to switch on germination in around 1,200 plant species across more than eighty genera worldwide, and karrikins are the key ingredient behind much of that effect. They were discovered here, in the very flora that leans on them hardest, and they carry a Noongar name wherever in the world they are now studied.

Hoarding seed, and holding your breath

Once you know to look for it, the bush’s compact with fire is written everywhere.

Those everlastings and orchids that flood a burnt patch the following spring? A great many were biding their time in a seed bank in the soil, dormant, holding out for precisely this moment: the fire clears the competing scrub, releases a sudden flush of nutrients into the ash, and the karrikins in the smoke give the long-awaited all-clear.

Others play a bolder hand still. Many banksias and hakeas practise what botanists call serotiny: they refuse to release their seed at all in ordinary times, instead hoarding it in tough, woody fruits held high in the canopy, sometimes for years on end, waiting. Only fire will prise those fruits open. When the heat finally cracks them, the seeds drop onto ground that has just been swept clean of competitors and fertilised by the burn. It is a strategy of extraordinary nerve and patience: give away nothing, year after year, and then spend your entire fortune in the single moment most likely to reward it. A banksia cone, in this light, is a strongbox, and fire is the only key.

The ancient icon that flowers from ash

And then there are the grass trees, balga, the slow, dark, ancient sentinels of the bush, and perhaps its most dramatic converts to fire. A grass tree’s blackened “trunk” is not wood at all but a tightly packed column of thousands of old leaf bases, bound together with the plant’s own resin, a resin so tough and useful that Noongar people prized it as a powerful adhesive for hafting tools and mending vessels. That resinous trunk is also what lets the plant shrug off a fire that would kill an ordinary tree.

These are plants of almost geological patience. A grass tree grows only a centimetre or two a year, can take many years to flower, and is said to live for centuries. The oldest individuals may have been standing, quietly, since before European ships appeared on the coast. And they are famous for flowering spectacularly after fire, sending up a single towering spear, dense with hundreds of nectar-rich flowers and mobbed by birds and insects. Curiously, researchers have found that the taller and older a grass tree is, the more likely it is to flower after a burn, as though the elders of the bush answer the fire first while the youngsters hold back. A field of blackened grass trees, each crowned with a flowering spire against the char, is one of the defining and strangely moving sights of the post-fire landscape: age, fire and renewal in a single frame.

The tree that catches fire without burning

No Kambarang is complete without the moodja, the Western Australian Christmas tree (Nuytsia floribunda), which, come the warm end of the season, sets itself alight with a blaze of orange-gold flower so vivid that from a distance a tree in full bloom can look as though it is burning. It is one of the largest plants in the world to live as a parasite: beneath the ground, it taps quietly into the roots of its neighbours, siphoning off water and nutrients, so that its own spectacular flowering is subsidised, in part, by the grasses and shrubs growing around it. A freeloader, admittedly, but a magnificent one.

To the Noongar people the moodja is far more than a spectacle. It is a sacred tree, understood as a resting place for the Kaanya, the spirits of the newly departed, on their journey. That belief lends its fiery flowering, arriving at the very peak of the wildflower year, a weight and a tenderness the tourist snapshot never captures. When the Christmas trees blaze gold along the roadsides at the tail of the season, the wildflower year is at its very height. In the oldest reading of this country, it is also keeping company with the dead.

The season with a name

All of this unfolds inside a calendar far older than the one on your wall. The Noongar people of the South West recognise six seasons, read from the land itself rather than from fixed dates: which flowers are out, which winds are blowing, what the animals and the sky are doing.

Two of the six belong to spring. Djilba, around August and September, is the first stir of the season: the cold snaps beginning to ease, the wattles turning the bush gold, the earliest flowers venturing out. And then comes Kambarang, around October and November: the great outpouring of colour, when the wildflowers reach their fullest abundance, the kangaroo paws and orchids peak, the grass trees flower, and the Western Australian Christmas tree begins to blaze gold along the roadsides. If you are walking through the bush in October, you are walking through Kambarang, the season the Noongar calendar has long known as the wildflower season.

It is worth holding both truths in the hand at once. The chemistry hidden in the smoke and the knowledge held in the calendar are describing the very same landscape: a country so long shaped by fire that its plants learned to build their whole lives around it, waiting for it, flowering for it, staking their futures on it. Seen that way, a wildflower season is more than spring arriving on schedule. It is one visible chapter of a long conversation between fire and flower, still going on, quietly, all around you.