Blackberries might be a tasty fruit, but as a plant they’re one of Australia’s most aggressive invaders. They damage the environment, reduce the usability of land, and create constant headaches for property owners. They’re one of the country’s most invasive weeds, spreading quickly and aggressively. Left to their own devices, blackberry thickets can choke native plants, drain resources like water and nutrients from soil, and create havens for pests.

Managing them isn’t just about keeping your garden tidy. In most states, landholders are legally required to control blackberries on their property. For homeowners, that means knowing how to tackle them effectively, and persistently.

Why Blackberries are a Problem

Blackberry infestations cause more trouble than many realise:

• Environmental damage: Blackberry canes grow into dense thickets that smother native plants and reduce biodiversity.
• Property impact: They block access to land, climb over sheds and fences, and can render areas completely unusable.
• Pests and vermin: The thick growth provides perfect shelter for foxes, rabbits, and even snakes.
• Legal obligations: Because they’re classed as a noxious weed, landholders must keep them under control or risk council action.

With such wide-ranging impacts, it’s clear that blackberries are more than just a backyard nuisance.

How Blackberries Spread so Quickly

Blackberries are notorious for how aggressively they take over land. Their long, arching canes can root wherever they touch the soil, allowing a single plant to sprawl into dense thickets. Birds and other animals also spread the seeds far and wide after eating the berries, helping new plants establish quickly. Once settled, blackberry bushes crowd out native plants and desirable garden species by competing for sunlight, water, and nutrients. This rapid growth is what makes early action so important; left unchecked, even a small patch can become unmanageable within a season or two.

Getting Rid of Blackberries

Physical Removal

For small infestations, mechanical control can be a practical starting point. Cutting back the canes reduces bulk and makes the patch easier to handle. Once cleared, digging out the crowns and as much root material as possible helps reduce regrowth.

However, blackberry roots are persistent. Even small bits left in the ground can re-sprout, which means follow-up is always required. Jim’s can help keep blackberries at bay with our professional mowing and slashing services, keeping on top of this over several seasons to gradually weaken the plants.

Herbicide Treatment

For larger or more established infestations, herbicides are often the only option. Sprays containing glyphosate or triclopyr are commonly used, but you need to use these under the right conditions:

• Plants should be actively growing, usually in summer through early autumn.
• Herbicide needs to reach fresh leaves for effective absorption.
• Cut-stump treatment, where canes are cut low and the herbicide applied immediately to the exposed stump, is especially effective on older plants.

Because herbicides can affect surrounding vegetation and waterways, care and precision are essential. Always follow label directions closely, or hire the help of a professional gardener to get the job done and protect the rest of your garden, too.

The Integrated Approach

The best long-term results usually come from combining physical and chemical methods. A common strategy is to slash canes to ground level, wait for regrowth, then spray the tender new shoots. This weakens the plant’s energy reserves and makes herbicide uptake more effective.

Persistence is the key, and it often takes several rounds of cutting, spraying, and monitoring before an infestation is completely eradicated. Without ongoing management, blackberries will almost certainly return.

Professional Blackberry Control

While it’s possible to manage a small blackberry patch yourself, larger infestations quickly become overwhelming. Clearing dense, thorny growth is physically demanding, and chemical control requires experience to apply safely and effectively.

That’s where professional help makes a difference. Jim’s Mowing teams have the tools and knowledge to tackle blackberry infestations of all sizes, from suburban backyards to rural blocks. With expert support, you can reclaim your land and keep it clear with ongoing maintenance.

Get in touch today, or head online for a free, no-obligation quote.