It's no secret to gardeners
that many Australian plants are adapted to respond to fire.
Some need the fire to help open up and release their seed.
And one of the most amazing things
that can happen in the landscape after fire
are those mass flowering events or ephemeral wildflowers
that absolutely blaze beautifully.
But something you might not know
is that the answer to this spectacle lies not in the heat of the fire
but in the smoke.
In the '90s, a group of scientists at Western Australia's Kings Park
sifted through the nearly 4,000 chemicals contained in smoke
to identify the individual compounds responsible.
And today, I want to show you
how you can harness those magical properties in smoke at home.
You're going to need a vessel for the fire,
a bucket with a lid,
some hose, water,
fuel for the fire,
vermiculite and seed
and a vacuum.
The first thing you need to do is make a small fire.
And you can do it in any vessel, really.
This is just a terracotta pot
but a kettle barbecue works really well too
'cause it's not a big hot fire you're trying to make.
It's a cool, smouldering, smoky burn.
Now, while that's burning down, I need to get ready
to capture those chemicals in the smoke.
And I'm gonna do it in a couple of ways.
The first one is by passing the smoke through some water.
I'm using this dust extraction bucket
which I've half filled with water.
And then I use a piece of hose
which will run right through this hole down to the bottom,
so it's actually submerged in the water.
Now that smoke is really cooking away there,
I'm gonna add this,
which is vermiculite.
It's very porous. And I want to use it to capture the smoke.
I'm just going to carefully sit that in the top there
and then on goes the lid.
Once the smoke is flowing, you simply connect the hose
from the fire to the bucket.
Connect the vacuum, which creates suction
to draw the smoke through the water,
and let it run for between 30 minutes and an hour.
All this while the vermiculite
is also absorbing the smoke in the fire pot.
(VACUUM MACHINE WHIRRS AND STOPS)
You can see the colour of that water has changed quite drastically
because all the compounds in the smoke have been absorbed by it
as the smoke passed through the water.
This is quite cool to touch.
Now I'm just gonna take these over to the propagation area
and show you how to use them.
Having some smoke-infused materials on hand
really is unlocking a key to propagation.
But the first thing I'm gonna use is the vermiculite.
I'm gonna mix a small amount in a potting media.
So that's going in there and then I'll mix that through
and then that goes straight into the cells.
And then I'm just gonna sow some seed on top.
(GENTLE GUITAR MUSIC)
A little bit more vermiculite.
That just sort of allows light in.
Holds that seed in place,
keeping it moist.
I've mixed a little bit of the smoke water,
just a small amount - about a cup - into a couple of litres of water
to water in my seedlings.
For all those destructive outcomes of fire,
there are, of course, some amazing regenerative properties,
and particularly for those plants that have evolved to thrive in it.
I've even read research that suggests
smoke can help grow bigger, better tomato seedlings.
So I reckon it's a really, really great process to have a go at.