What Should I Plant in Full Sun? The Best Plants for Hot, Sunny Australian Gardens

“Full sun.”

Two words on a plant label that make gardening sound considerably simpler than it actually is.

Technically, a plant described as suitable for full sun generally needs a good amount of direct sunlight to perform well. But anyone who has gardened in Australia knows there is full sun... and then there is FULL sun.

Six hours of sunshine in a protected coastal garden is not the same growing environment as a west-facing garden bed beside a Colorbond fence in January. A sunny garden in Hobart is not experiencing what a sunny garden in western Sydney, Brisbane or inland NSW is experiencing. Add reflected heat from paving, dry soil, hot winds or a brick wall and you've created something quite different again.

This is why people can buy a plant labelled “full sun”, put it in full sun and still watch it slowly cook.

The label wasn't necessarily wrong. We just asked a much bigger question than two words could answer.

So if you've got a garden that absolutely bakes, here's what I'd look at before buying anything.

First, work out what “full sun” means in your garden

Before you start choosing plants, spend a day watching the light.

It sounds ridiculously basic, but people are often surprised by what they find. A garden bed they describe as full sun might receive direct sunlight from 8am until midday and then be shaded by the house. Another might sit quietly in shade all morning before getting absolutely belted by western sun from 1pm until sunset.

Those aren't equivalent positions.

Morning sun is generally gentler. Afternoon sun arrives when temperatures are already high and surfaces around the garden have been absorbing heat for hours. If the bed sits beside paving, concrete, brick or metal fencing, plants can also receive radiant heat from those surfaces.

This creates a little microclimate.

Your suburb might have one weather forecast, but your backyard can contain half a dozen different growing environments.

That's why the bloke three streets over can grow something beautifully while yours looks personally offended by where you've planted it.

Sun isn't always the thing doing the damage

This is an important distinction.

When a plant scorches in a sunny position, it's tempting to conclude that it doesn't like sun. Sometimes that's true. Sometimes the real problem is that the root system couldn't supply enough water to the leaves under the conditions it was experiencing.

Plants lose water through tiny openings in their leaves called stomata. That process is part of transpiration. On hot, dry or windy days, water loss can increase substantially. If the roots can't keep pace — perhaps because the plant is newly planted, the soil is dry, the root zone is restricted or the conditions are simply extreme — the plant becomes stressed.

So “sun tolerance” isn't only about leaves being able to withstand sunshine.

The whole plant has to cope with the environment.

A well-established plant with roots exploring a decent volume of soil is in a very different position from a tube planted three weeks ago whose roots are still sitting close to the original root ball.

This is why even very tough plants need looking after while they establish.

Look at the leaves. Plants often tell you how they cope.

Once you start noticing foliage, hot-climate plant adaptations become fascinating.

Many plants adapted to exposed conditions have relatively small leaves. Smaller leaves can reduce the surface area exposed to intense conditions. Others have waxy surfaces, hairs or pale and silvery foliage that can influence how the leaf interacts with sunlight and water loss.

Succulent plants take another approach and store water in fleshy tissues.

Then you've got the fine, tough foliage we associate with many Australian natives and grasses.

None of these features automatically guarantees that a plant will survive every hot garden in Australia, but they give you clues.

This is one of the reasons I love Eremophila for hot Australian gardens.

You look at a plant like Blue Horizon™ Eremophila and the foliage is already telling you half the story.

Blue Horizon™ Eremophila deserves more attention

There are plants people buy because they're flowering beautifully on the day they visit a nursery.

Then there are plants you appreciate more every year they're in the garden.

Blue Horizon™ Eremophila falls into the second category for me.

Its silvery-blue foliage brings a completely different colour into a garden, which means it's doing something useful even when you're not thinking about flowers. Against ordinary green foliage, that silver-blue colour creates contrast immediately.

And this is where choosing plants for hot gardens gets more interesting than simply finding things that won't die.

Survival is a fairly low bar.

We still want a beautiful garden.

If you're building a hot, sunny planting, combining different foliage colours and forms can create far more interest than relying on flowers alone. Silver Eremophila beside deep green foliage, for example, gives you contrast all year rather than for a few weeks.

That is a much better return on your garden space.

Thriver™ Eremophila is another one for the tough jobs

There are parts of a garden where the brief isn't particularly romantic.

It's basically:

Please grow here and don't carry on.

That's where tough plants earn a following.

ThrivR™ Eremophila is another option worth looking at for suitable hot, sunny landscapes. Eremophilas as a group are closely associated with Australia's drier environments, although individual species and cultivars still have their own requirements, so it pays to choose the actual plant rather than assuming every Eremophila behaves identically.

That last bit matters across horticulture.

“Native” doesn't mean drought-proof.

“Eremophila” doesn't mean suitable for every soil.

“Full sun” doesn't mean invincible.

Plant names give us clues. The specific cultivar and site give us the useful answer.

Westringia is popular in sunny landscapes for a reason

Poor old Westringia suffers from being successful.

We see it everywhere, so people sometimes dismiss it as boring.

But plants don't become widely used in landscaping by accident.

Selected Westringias can handle exposed conditions well, their evergreen foliage provides structure throughout the year, and the sheer range of growth habits now available makes them much more versatile than the big old shrubs many people picture.

Grey Box™ Westringia can give you compact structure. Goldie Box™ adds a different foliage tone. Low Horizon™ gets down closer to the ground and spreads. Mundi™ can occupy a broader, lower part of the planting.

That means we can use one general group of plants to solve several completely different design problems.

And because their foliage isn't screaming for attention, they work brilliantly with plants that are.

Every garden needs a few people willing to be the supporting cast.

Lomandra is not just a car park plant

Lomandra has suffered a similar fate.

It's tough enough to be planted around shopping centres, roadsides and commercial landscapes, and somehow we've interpreted that as evidence that it doesn't belong in beautiful gardens.

I'd argue the opposite.

If a plant can survive a car park, perhaps we should be listening.

The trick is choosing the right Lomandra and using it properly.

Tanika® Lomandra gives you fine, arching foliage and movement. Lime Tuff™ brings a brighter green. Tropic Cascade™ has a softer, more cascading appearance.

Mass them rather than sprinkling one of each around the garden and suddenly they stop looking like utility plants.

They become design.

The foliage moves in wind, catches light differently throughout the day and provides a completely different texture from compact shrubs.

And unlike flowers, that texture isn't seasonal.

Kangaroo Paws were built for a bit of drama

If the previous plants are doing the sensible work, Anigozanthos Regal Velvet can bring some theatre.

Kangaroo Paws are one of those Australian plants that don't really look like anything else. Their upright flower stems create vertical accents through a planting, and that shape becomes particularly useful when much of the surrounding vegetation is rounded or spreading.

This is another design lesson worth stealing.

When everything in a garden has roughly the same height and shape, adding one strongly upright form can change the entire composition.

You don't necessarily need more colour.

Sometimes you need a different line.

Give Kangaroo Paws the conditions they like and use them where those flower stems can rise through lower planting rather than getting lost amongst equally tall shrubs.

Now you've got layers.

Purple Fountain Grass changes the mood completely

Hot sunny gardens don't have to look like the Australian bush.

You can take exactly the same environmental problem and create a completely different aesthetic.

Purple Fountain Grass, where appropriate for your area and situation, brings dark foliage and movement. Suddenly the planting feels richer and moodier. Put dark foliage beside silver and the contrast becomes even stronger.

This is why I wouldn't start designing a full-sun garden by asking, “What flowers can I have?”

I'd ask:

What shapes do I want?

What colours of foliage?

Where do I need height?

Where do I want movement?

Where does the eye need somewhere to rest?

Then add flowers.

It produces a garden rather than a flower display with mulch underneath.

And then there are the plants that basically carry their own water bottle

Succulent foliage is another completely different strategy.

Dwarf Blue Chalk Sticks is a great example. Those fleshy blue leaves store water, while the colour gives you another opportunity to break up a sea of green.

Plants like this are particularly useful visually around rocks, gravel and contemporary landscapes because their foliage has such a strong shape.

But here's an important warning: drought tolerance and poor drainage are not the same thing.

Many plants adapted to drier environments cope beautifully with periods of low rainfall but resent sitting in persistently wet soil.

Which brings us to one of the most overlooked parts of creating a hot, dry garden.

Drainage still matters when the garden is dry

It sounds contradictory.

If the problem is drought, why are we talking about drainage?

Because roots need oxygen.

A garden can be bone dry in summer and waterlogged after prolonged rain. Heavy soil, compaction and poor site drainage don't disappear just because you've chosen drought-tolerant plants.

Some of the plants we associate with dry conditions are particularly unhappy sitting wet around the roots.

So before you create a “drought-tolerant garden”, understand the soil.

Does water disappear quickly?

Does it sit after rain?

Is the ground compacted?

Are you gardening on sand, loam or heavy clay?

The best plant for a hot sandy garden may not be the best plant for a hot clay garden.

Same sunshine.

Completely different underground world.

Don't plant a drought-tolerant plant and immediately test the theory

This one deserves saying again because we see it so often.

You buy a tough plant.

You plant it.

You decide it's drought tolerant.

You stop watering it.

The plant dies.

You declare it not very drought tolerant after all.

A newly planted plant doesn't have the root system of an established plant. Until its roots have moved into the surrounding soil, the amount of water available to it can be surprisingly small.

This is especially important with tubestock.

Tubestock can establish beautifully because young roots can move into surrounding soil quickly when planted and cared for correctly. But that small starting root ball also means you need to pay attention during establishment.

Water the root zone, not just the general vicinity.

Check the soil rather than assuming.

As roots spread and the plant establishes, its ability to use moisture from a much larger volume of soil improves.

That's when its natural toughness starts doing more of the work.

Mulch helps, but don't build a volcano

Mulch can be extremely useful in sunny gardens because it helps reduce moisture loss from the soil surface and buffers soil temperature.

Just don't pile it against the crown or stem of the plant.

I don't know who started the mulch-volcano trend, but plants didn't ask for it.

Leave a little breathing space immediately around the base and spread mulch across the surrounding soil at an appropriate depth.

The point is to protect the root zone.

Not bury the plant.

A tough garden doesn't have to look tough

This is probably the biggest misconception around hot, low-water gardens.

People picture gravel, spiky plants and six shades of grey.

And if that's your thing, fantastic.

But you can also build something lush-looking.

The trick is density and contrast.

Imagine the silver-blue foliage of Blue Horizon repeated through a bed, fine green Lomandra moving between it, compact Westringias providing structure and something like Kangaroo Paw punching flower stems up through the planting.

Add a low spreading layer at the front — perhaps Aussie Rambler™ or another groundcover suited to the site — and suddenly you've got a garden that looks full and generous.

Nothing about it says “we gave up watering”.

It just says the plants belong there.

The hottest part of the garden can become the best bit

We tend to think of difficult sites as compromises.

The horrible western bed.

The baking driveway.

That strip beside the fence where everything fries.

But difficult conditions force you to stop buying plants purely because they're pretty and start understanding what they actually need.

And weirdly, gardens often get better when we do that.

You start noticing foliage.

Growth habits.

Soil.

Water movement.

Root systems.

Microclimates.

You stop trying to convince plants to tolerate a spot and start choosing plants that have a fighting chance of enjoying it.

That's the whole game, really.

The best full-sun garden isn't the one filled with the toughest plants you can find. It's the one where tough plants have been matched to the right kind of tough.

Because Australia doesn't have one version of full sun.

And thankfully, we don't have one version of a full-sun garden either.