Written by:Nathan Schwartz
Published on:October 4, 2022
Updated on:February 22, 2024
Native to Southeast Australia, the black wattle is one of the most commonly grown bush tucker foods in the country, with gorgeously scented creamy pompoms of flowers in late winter and early spring.
Growing black wattle in Australia is pretty straightforward, but it will need controlling if you plan on growing it as a crop, with mature trees reaching 10m tall.
If you want to know how to grow black wattle, you’ve come to the right place. We’ve got all you need to know about growing this stunning native tree, and how to harvest its seeds when they’re ripe.
More...
Acacia mearnsii (Black Wattle) Australian Native Guide
What is Black Wattle?
Natural Habitat of Acacia mearnsii
How to Grow Black Wattle Tree
Best Conditions to Planting Black Wattle
Caring for Black Wattle Tree
Ways to Propagate Black Wattle Tree
How to Harvest Black Wattle
Black Wattle Pests and Diseases to Look Out For
Black Wattle Frequently Asked Questions
Add More Native Plants to Your Garden by Growing Black Wattle Trees
Family: | Fabaceae |
---|---|
Genus: | Acacia |
Species: | mearnsii |
Common Names: | Black wattle, Wattleseed, Green Wattle, Late Black Wattle |
Location: | Outdoor |
Type: | Tree |
Growth: | up to 10m tall |
Sun requirements: | Full sun |
Foliage Colour: | Green |
Flower Colour: | Creamy white |
Flowering: | Winter and Spring |
Fruit: | Edible seeds |
Maintenance level: | Low |
Poisonous for pets: | Non-toxic to cats and dogs |
What is Black Wattle?
Source: en.wikipedia.org
Black wattle is a variety of wattle endemic to its native habitat in southeast Australia. It is part of the Acacia genus. Acacia mearnsii produces easily identifiable creamy white flowers at the ends of its branches in late winter.
Its foliage is similar to mimosa, with palm-like fronds holding delicately divided, symmetrical, evergreen leaves that add structure and drama to any garden.
The edible seeds of Acacia mearnsii, or black wattle, are harvested when the seed pods turn brown and begin to open in late spring or early summer. They have a wonderfully nutty flavour with hints of chocolate and coffee when roasted.
See our in depth guide to growing Acacia including the best varieties to grow in Australia.
Natural Habitat of Acacia mearnsii
Black wattle grows best in an exposed position, in full sun, and makes a great wind barrier for suburban gardens. They are drought tolerant but will need extra water and a light mulch if you intend to harvest the seeds every year.
How to Grow Black Wattle Tree
Black wattles are short-lived trees, typically reaching their full height of around 10m in under ten years. With proper care, they can live for around thirty years in cultivation but will need regular pruning and support as their limbs grow brittle with age.
Source: apps.lucidcentral.org
Best Conditions to Planting Black Wattle
The best way to plant black wattle is to buy a young tree from a local nursery or online. Check that the roots are healthy, and not curling around the pot. If they are, tease them out gently to encourage outward growth.
Then plant black wattle in a hole twice the size of the container, and make sure the soil is well drained.
Light & Temperature
Black wattle grows well in any part of Australia and can cope with droughts just as well as brief frost spells. However, young trees should be planted with protection, and if frosts are predicated, it’s wise to add a thin layer of mulch to maintain the soil temperature, at least for the first couple of years.
Get Your Free Guide:
Master Growing Australian Natives eBook
A Must Have Complete Guide for Every Australian Garden
Get Your Free Guide:
Master Growing Australian Natives eBook
A Must Have Complete Guide for Every Australian Garden
Yes, I want the FREE guide
Yes, I want the FREE guide
Choose a bright, sunny location that gets at least 6 hours of full sun each day, as this helps black wattle seeds to ripen sooner after flowering.
Here is our list of different types of mulch and including their pros and cons.
Soil & Moisture
Black wattle needs good drainage. If you have clay soil, consider growing black wattle in a container, or a raised bed. If that’s not an option, dig plenty of grit or sand through the soil before planting.
After planting, water black wattle trees generously to create good root contact, and then water them once a week for their first summer while their roots are getting used to more open space and drier conditions.
Exposure
Black wattle is happiest when exposed to the elements, with high winds generally seen as a positive. As such, black wattle makes great screening, even in coastal gardens.
Caring for Black Wattle Tree
Source: keys.lucidcentral.org
Pruning Late Black Wattle
Black wattle does not need pruning but can be trained into a smaller shrub by cutting back half the branches each year, leaving the newest branches in place.
This will eventually create a shrubby form, and prevent it from getting too tall in small gardens.
Mulching & Feeding Black Wattle
Black wattle doesn’t need much in the way of nutrients but will produce healthier flowers, and more abundant fruit with high potassium, and high phosphorus feed.
As young plants develop, nitrogen mulches or granular fertilisers will help them grow, but after the first few years, you should focus more on seed production.
A generous mulch of garden compost, once every three years, is more than enough but can promote moisture retention unnecessarily, so use granular fertilisers and liquid feeds where possible.
Repotting Black Wattle Tree
If you notice that your black wattle has developed yellow leaves, it might be time to re-pot it. For black wattle in the ground, this isn’t an issue, but container-grown black wattle quickly exhausts their nutrients, and roots will begin to wrap around themselves, causing nutrient deficiencies.
Simply remove black wattle trees from their pots, tease their roots gently to encourage new growth, and plant them into fresh, gritty compost in a bigger container.
Ways to Propagate Black Wattle Tree
Propagating black wattle from seed and cuttings is straightforward, and far easier than many guides suggest. Avoid propagating in darkness, which will speed things up, but produce weaker plants that take longer to truly establish.
Source: yarraranges.vic.gov.au
Propagating Black Wattle from Seeds
To propagate black wattle seed, you will need to use fresh seed, or soak dried seed for up to 24 hours to revive it.
- After soaking, or podding your wattleseed, mix compost and perlite in equal measure in small, 8cm pots.
- Sow two seeds on the surface of each pot, and cover lightly with perlite to exclude some light.
- Water each pot until the compost is evenly moist.
- Leave pots in a sunny position for up to a month, misting, or watering gently when the soil starts to dry.
- After germination, remove the weakest seedling and continue watering the strongest seedling.
- After a couple of months, your seedling will have healthy roots. Move it to a bigger pot, filled with a similar mix of compost and perlite for drainage.
- Plant in the garden when your black wattle is 2-3ft tall and has clearly defined foliage.
Black Wattle Propagation from Cuttings
Black wattle is not naturally predisposed for cuttings, but can easily be encouraged with the right tools, and method.
You will need:
- Small pots
- Perlite
- Garden soil or spent compost
- Rooting gel
- Sharp secateurs - see our product review of the best secateurs available online.
Greenwood, or softwood cuttings are the most effective part of the plant for rooting, so choose new, non-flowering stems from this season’s growth just after the rest of the plant has finished flowering (flowering stems will not root properly).
- Cut just below a node (where a leaf meets a branch) roughly 15cm from a shoot tip.
- Remove all but the top-most leaves, and dip the cut end in rooting hormone. (Find out the different types of rooting hormones here.)
- Gently push your cutting into a pot filled with an even mix of perlite and garden soil or spent compost (the lower the nutrient levels, the better).
- Place your cutting somewhere warm and bright, but out of direct light. By the end of summer, it should have begun to root. Test by gently pulling each cutting. If there is resistance, then there are roots.
How to Harvest Black Wattle
A few weeks after flowers have dropped, you should see green, pea-like pods, starting to develop. Over the next few weeks, those pods will swell as seeds grow inside them. By early summer they will begin to turn brown.
When the first dry wattleseed pods begin to open, it’s time to harvest. Grab a bag, bucket or basket, and start pulling the pods, one by one, from the tree.
Finally, open up the pods, remove the seeds, then leave them to dry on a windowsill, or drying rack, or roast them slowly in the oven.
For more information on how to use wattleseed, check out ourguide to preparing and using wattleseed.
Black Wattle Pests and Diseases to Look Out For
Like most Acacia species, black wattle is native to Australia and well adapted to cope with our climate, making it a great low-maintenance tree that doesn’t suffer from common pests or diseases.
Blackfly and aphids can damage young growing tips in early spring, so keep an eye out, and simply wash them off with a hose. Black spots on the leaves may develop as a side effect of aphids and blackfly, caused by a fungus called anthracnose. Simply remove spotted foliage to prevent the spread of infection.
Black Wattle Frequently Asked Questions
Is black wattle invasive?
Black wattle is a native species across south-eastern Australia, and therefore not considered invasive. However, due to its rapid growth, and mass seed production, it can take over gardens, so should be managed appropriately, and planted more than 10m from buildings.
What can you use black wattle for?
The timber from black wattle is an effective firewood and can be coppiced for log burners and fire pits. The seeds are edible, with a lightly spiced coffee flavour, and are commonly used in baking.
Do ticks live in wattle trees?
The Wattle tick scale is a scale insect, rather than a tick, and is more common in rural settings. If you notice tick-like insects under the bark of wattle trees or gather around the base of leaves, they are not harmful to humans but should be removed to prevent damage to the plant.
Are wattle trees good for new build properties?
Wattle trees are beneficial for any garden where the soil has been compacted, disturbed, or otherwise harmed. Their roots are fast-growing, and the trees are relatively short-lived, so work well to create structure quickly, while helping to regenerate the soil structure beneath them.
Add More Native Plants to Your Garden by Growing Black Wattle Trees
Growing black wattle is a great way to bring native plants into your garden with very little effort. Its flowers are great for pollinators and packed with nectar, and its seeds make great bush tucker. As well as the benefits to wildlife (and the kitchen) black wattle is a practical tree for screening and wind protection.
OK, so black wattle might be an easy self-seeder, and its roots are far from friendly, but when you weigh the pros and cons of black wattle as a garden tree, I firmly believe that the pros outweigh the cons.
So what are you waiting for? Grow black wattle and discover the joys for yourself.
Published on October 4, 2022 by Nathan Schwartz
Last Updated on February 22, 2024
Related Posts
How to Grow Plumcot Trees in Australia
might sound like a gimmick, but they’re a fairly natural ...
Seablite (Suaeda australis) Bush Tucker Guide
is an incredible plant for foragers and elevates any bush ...
Sea Parsley (Apium prostratum) Bush Tucker Guide
Apium prostratum, commonly known as native sea parsley or sea ...
Maroon Bush (Scaevola spinescens) Growing Guide
Maroon Bush, or the Prickly Fan Flower, is an entirely ...
About the author
Nathan Schwartz
Hey, I'm Nathan Schwartz, team member at Aussie Green Thumb since 2020. I have a passion for edible plants and Australian native plants, both in the garden and in the Aussie bush. As an avid traveller and camper, I love seeing the different landscapes and flora that Australia has to offer, and try to incorporate this into my own daily living. Whether I am living on the road, in an apartment or have a big backyard working with practical and usable gardens in small spaces is my specialty.
Leave a Reply
My young wattle flowers in small yellow balls. I planted it in a shady area 3 years ago. It has grown like a pencil (seeking the light) – about 8 metres tall, flowering only in the top 1 metre. .
Thinking of coppicing it, to get flowering closer to the ground, notwithstanding it is quite shady there.Is this possible, and what height from the ground should I cut? Thanks, Pete .Hi Pete,
Acacia responds really well to coppicing. It’s not the most resilient tree in the world though, so cut back in spring, not autumn, and leave about a foot of trunk at the base so it’s above any puddles of water.
As soon as you cut back acacia it triggers a nitrogen release from the roots, which it reuptakes to promote fresh stems. They’re fascinating trees, and coppicing can be done pretty regularly to keep them looking bushier.
Like any coppices tree, the shape will never quite be a good as a tree that was grown as a multi-stemmed specimen, but if you cut back about half the stems every few years and alternate that, it should keep a really lovely shape, with much more flower and foliage nearer the ground.
Best regards,
Gary Clarke