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Plants and Trees that Grow in Clay Soil in Australia

What you have to remember with heavy clay soils is that some nutrients are bound by the clay particles and won’t be available for the plants to take up.

If you have to deal with clay soil in your garden, don’t worry because there are plenty of trees and plants that will thrive in this type of soil.

I’ve dealt with clay soils in the past and apart from being hard to work, I really didn’t have a problem with growing a whole range of plants. 

What you have to remember with heavy clay soils is that some nutrients are bound by the clay particles and won’t be available for the plants to take up. Therefore, whenever you can, you should lay a thick layer of mulch over the soil.

mulch around plant | Plant care

That’s precisely what I did in my last garden and over time, the mulch will break down and help to enrich the soil and also improve the structure.

How to plant in clay soil

Before I list some plants that you should consider growing if you have clay soil, here are some tips for planting into the soil.

Don’t try to plant anything when the soil is either very wet or completely dry. You will find it extremely hard to dig a decent hole and waterlogged soil will rob your new plant of vital oxygen.

When planting, dig a large hole. The hole should be around 3 times the size of the rootball of the plant. You might need to use a mattock rather than a spade to create this size hole in clay soil.

planting tree in a hole | Plant care

Add some gravel or coarse sand into the bottom of the hole to help increase the drainage.

You should add a good amount of organic matter to the bottom of the hole as well. Hill up some of this organic matter into a small mound that you place the roots of the plant over.

Backfill the hole with the soil that you’ve excavated but try to break it up as much as you can first. Create a moat around the plant and fill this with water. 

This will allow the water to eventually soak down to the roots of the plant rather than running straight off the surface. 

Make sure you cover the soil with a thick layer of good-quality mulch but keep this a little away from the base of the plant.

Now that you know how to plant in clay soil, here are some plants that will thrive in this type of soil.

Crepe myrtles (Lagerstroemia)

Crepe Myrtle Lagerstroemia Indica | Plant care

If you’re looking for an attractive tree that has an abundance of flowers and will grow happily in clay soil, look no further than the crepe myrtles.

These trees won’t mind the clay soil and will provide you with a nice shade tree in summer as well as lots of colour in summer.

Callistemon shrubs and small trees

As Callistemon are natives, they’re quite used to growing in clay soil and will actually thrive and colour your garden with their gorgeous bottlebrush flowers during many months of the year.

Some hardy varieties to grow include:

  • Little John
  • Firebrand
  • Rosy Morn
  • Kings Park Special
  • All Aglow
  • Taree Pink

Melaleucas 

Melaleuca viminalis hot pink | Plant care

While some melaleucas grow naturally in coastal areas with sandy soils, there are others that will grow quite happily in clay soils. 

Many of these will grow either as large shrubs or small trees and have brightly coloured new foliage and clusters of attractive flowers.

Hardy varieties to try include:

  • Melaleuca linariifolia ‘Claret Tops’
  • Melaleuca hypericifolia ‘Ulladulla Beacon’

Leptospermums

Leptospermum laevigatum Coast Tea Tree | Plant care
Leptospermum laevigatum (Coast Tea Tree) / Photo by Stephen Bain / Wikimedia / CC BY-SA 3.0

Leptospermums are somewhat similar in growth to melaleucas and the two species are often confused.

More commonly referred to as tea trees, these species are characterised by their fine and slender leaves and brushy flowers in a range of colours.

A popular variety is Leptospermum petersonii ‘Little Lemon Scents’. This has quite a compact growth habit and lemon-scented foliage. 

Lomandra

Lomandra longifolia | Plant care
Lomandra longifolia / Photo by Daderot / Wikimedia / CC0 1.0

Lomandra is a native clumping grass species that does really well in clay soils. It can be grown as a specimen plant or even as a useful border plant along a driveway. 

One species, Lomandra longifolia, is prized for its attractive growth habit and perfumed flowers. It can be left to grow naturally but also lends itself beautifully to being cut back to keep it somewhat more compact.

Scaevola

Fan Flower | Plant care

For a hardy groundcover, you can’t go past the native Scaevola or fan flower with its dense green foliage and attractive purple flowers. You can use this plant to cover a large area in a sunny spot in the garden.

Grevilleas

Grevillea ‘Peaches and Cream | Plant care

For areas with low rainfall, grevilleas are ideal for growing in clay soils. However, most grevilleas don’t like waterlogged soils so select a variety that grows naturally in your region.

Pandorea jasminoides

Pandorea jasminoides | Plant care

This native climber is great for growing in clay soil. It has lovely bright green foliage and soft white flowers with a deep pink centre.

This vigorous climber will cover any structure fairly quickly as long as you provide some support such as a trellis.

Roses

roses 1 | Plant care

I’ve grown many different types of roses in clay soils and they have all performed magnificently.

As long as you give them additional water during dry periods and mulch them heavily, roses will perform exceptionally well in clay soils.

Photo of author

Annette Hird

Annette Hird is a gardening expert with many years of experience in a range of gardening related positions. She has an Associate Diploma of Applied Science in Horticulture and has worked in a variety of production nurseries, primarily as a propagator. She has also been responsible for a large homestead garden that included lawn care, fruit trees, roses and many other ornamental plants. More recently, Annette has concentrated on improving the garden landscape of the homes that she has lived in and focused a lot of energy on growing edible plants as well. She now enjoys sharing her experience and knowledge with others by writing articles about all facets of gardening and growing plants.

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4 thoughts on “Plants and Trees that Grow in Clay Soil in Australia”

  1. Hi Annette.
    Thanks so much for this article and the tips! I have learnt a lot. I am planning to plant an avo tree that I’ve had in pots for 6 years and have discovered that the soil where I want it, is very much like clay with a lot of rocks as well. Will an avo tree manage to grow here if I plant it as per your recommendations? Also, I am wanting to put some Lily Pillys next to it. Would they be okay? Thanks so much for your time!

    Reply
    • The soil doesn’t sound ideal for your avocado tree which prefers free-draining soil with lots of organic matter. Without seeing the soil, my first recommendation would be to try and improve it first before planting anything. Gypsum will help to break up clay but it will take some time. Another thing I’ve found really useful for improving clay soils is to cover it with a layer of acacia mulch. As this breaks down, it will greatly improve the soil structure and add valuable nitrogen. Once again, this will take time. I wouldn’t risk planting your avocado there after you’ve spent 6 years nurturing it in the pot. As far as the Lily Pillys go, I would just test with one plant to see how it handles the conditions. I often do this with plants in different locations and then move them if they’re not doing well. Hope that helps a little.

      Reply
  2. Thanks for this it’s much appreciated. I have about 2000 sq m of soil that has a lot of clay mixed in it. This was dumped on my property when I was away probably somewhere around 12 dog and truck loads. Had to spread the dumped loads. This resulted in some 15 gum trees dying and I have bought some sugar gum seedlings to plant. Can I plant the seedlings in raised mounds with a native mix and garden mate (mineral rock ground) spread on the clay soil? Thanks would appreciate your comment. Bert Dunsford

    Reply
    • Hi Bert

      My first recommendation would be to do a soil test of the soil that was dumped on your property and not plant into until you know what you’re dealing with. Gum trees are incredibly hardy, so you need to know both the pH and the nutrient concentrations in the soil. Rather than do a soil test yourself, I would send a sample to a laboratory to get an accurate indication of what’s in the soil.

      Reply

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