Whether you're getting started on a small home vegie patch
or you've got something market garden-sized like me,
it's important to get to know your soil
before you start dropping plants into the ground.
It will certainly save you time, money and a fair bit of grief.
When I moved in down here,
I didn't take soil samples and send them off to the lab,
I talk to my neighbours about what to expect in the soil.
And I dug a few test holes to find out for myself.
Soil is rarely uniform and it can vary across even a small site.
So it's a good idea to dig a couple of holes around half a metre deep.
First off, let's have a look at the profile.
And my soil is pretty typical of soil in many parts of Australia.
I've got my topsoil layer.
And underneath that is grey band, that's my subsoil.
And then right at the bottom I've got my clay base.
The topsoil is full of living organisms -
earthworms, beneficial bacteria and fungi that make for good soil health.
It's important to routinely add organic matter
to feed this top layer.
Then there's your subsoil.
It has less life, but plays a role
in how well a plant's roots absorb nutrients
and how well it drains.
Then finally, at the bottom of the hole,
there's usually a layer of nutrient-rich clay.
Now, when you cultivating your soil,
it's important not to mess up the profile.
Otherwise, you'll bring your clay to the top,
forming a layer that roots and water find it hard to get into
and you'll be burying your valuable topsoil.
Now, you can see in this area quite clearly
where the clay has been brought to the surface,
where a big hole has been dug in the past
and the water is just sitting around
because it's got nowhere to go
and can't find its way through that hard layer.
So what we've done is we've planted a dense crop of broad beans,
not for eating, but to dig back through the soil.
And we'll continue to put in green manure crops
to rehabilitate this site and make the soil come up lovely.
It'll be ready to plant in.
I was sold on this place
when I discovered it had deep, black topsoil across the whole property.
Black indicates organic material
and organic material brings fertility.
Dark brown, red and tan top soils
get their colour from iron and aluminium oxides.
They're generally regarded as having a good amount of organic material
and they provide good drainage.
Pale and whitish soils often occur in high rainfall areas
and are leached of nutrients.
Yellow soils generally have a decent amount of organic material
but they easily become waterlogged.
Green, blue or bluish-grey soils are the worst.
They have low amounts of organic material.
They don't drain well and they become easily compacted.
Back to my black soil.
Although black signifies the presence of organic matter,
it can also signal poor drainage.
And when I came here to make sure my soil was well drained,
all I had to do was smell it.
It smells fresh like a walk through a rainforest,
which means it's good.
If it was poorly drained,
it would be anaerobic and it would smell pretty bad.
As bad as rotten eggs.
The best soils contain a balance of silt, clay and sand
and are generally known as loam.
If you wet your soil between your fingers,
the sand feels gritty, the silt feels like moist talcum,
and the clay, well, that's slippery.
Too much sand and your soil is gonna be well drained,
but it's not going to hold a lot of nutrient.
Too much clay, and the opposite will occur.
You'll get a lot of nutrient,
but the soil will become waterlogged very easily.
And too much silt,
well, your soil will be hydrophobic and prone to erosion.
But you can correct these problems.
First of all, by adding organic matter like compost.
Joy and I have our own brew.
(ENGINE STARTS)
As well as green waste from the farm,
we're using coffee husks from a local roaster,
charcoal that we make ourselves, and chicken manure.
Joy's turning it all in to keep it oxygenated
so it breaks down quickly and evenly.
You'll find lots of other solutions for correcting problems soils
on our Gardening Australia website.
And you should also put in some green manures through your soil
if you really want to keep it humming along.
But get to know your soil.
Have a look at the colour, feel it,
smell it,
and you'll be surprised what it can tell you.