Ever stood on your lawn, admiring the lush greenery and perfect mow job… only to notice there’s a patch of unwanted plants popping up on the side?
Weeds are the bane of any proud lawn owner, and keeping them out of your yard can feel like an uphill battle. That’s where products like weed killers or herbicides come in.
But with so many on the market, how do you know what to pick? Worry not – we’ve rounded up our picks for the best weed killer in Australia based on the type or use of the product.
No need to wade through the weeds to find the best herbicide for your lawn. Take your pick, then get ready to get down and dirty!
What is a Weed, Anyway?
There aren’t any specific species or types of plants that are specifically considered a “weed.” Instead, weeds are simply plants that grow where they aren’t wanted.
These plants can be native or non-native, and invasive or non-invasive. They’re unwanted because they take up valuable nutrients and space that would otherwise go to your lawn and garden plants.
Common weeds in Australia include bindii, oxalis, clover, capeweed, and nutgrass. Mint, when planted outdoors, can quickly become an invasive weed as it spreads very easily.
However, it’s important to know that some weeds are beneficial to the environment. They could be important for pollinators and other wildlife.
You can consult with a professional gardening service about tackling weeds in your lawn – and also how you can maybe allow a little wildness to benefit your local ecosystem.
What Causes Weeds in a Lawn?
Weeds can grow on your lawn for a number of reasons. They’re opportunistic plants, and can sprout up due to causes like:
- Compacted lawns
- Overwatered lawns
- Poor mowing habits
- Fungi and other diseases
- Underwatered or drought-stressed lawns
- Imbalanced soil nutrition (such as too-low nitrogen)
- Seed drift or growth from neighbouring lawns
Types of Weed Killers
Weed killers or herbicides are products that – as the name suggests – kill weeds in your lawn.
Most weed killers can be broken down into three major types: pre-emergent, selective, and non-selective.
There are also natural methods for weed killing that do not involve products.
Pre-emergent weed killers
Pre-emergent herbicide targets weeds and invasive plants before they start germinating. It typically works by forming a protective barrier in the soil to stop unwanted seedlings from growing.
This type of weed killer doesn’t affect your existing grass, and typically lasts about 3 months.
Pre-emergent herbicide is best applied in winter to prevent any weeds from appearing in spring.
If you’re top-dressing your lawn or reseeding bare patches in your lawn, wait until the new grass has germinated before applying the herbicide.
Selective weed killers
Selective weed killer affects only specific types of weeds, depending on the ingredients. It will target the metabolic process of these unwanted plants, while leaving your lawn grass alone.
Most selective herbicides target things like clover, creeping oxalis, and bindii.
Always double-check the ingredients and applications of any product. Many broadleaf weed killers affect buffalo grass.
What are the advantages of a selective herbicide? It allows for more targeted and specific weed control, since you can adjust the application and timing as necessary.
However, they may not target all the weeds in your garden and may require a wetting agent to be fully effective.
Non-selective weed killers
Non-selective weed killer, on the other hand, kills any plant life it comes into contact with – meaning this weed killer will kill everything. These herbicides typically contain ingredients like glyphosate, dicamba, or nonanoic acid.
What are the benefits of a non-selective herbicide? It tends to be more cost-effective and can target any and all unwanted plants. It’s also best if you want to kill off your old lawn before seeding with new grass or laying new turf.
However, you’ll need to be extra careful with your application. Weather conditions can cause spray drift, harming other plants or the surrounding ecosystem.
Ingredients in non-selective herbicides can also damage the soil with prolonged use.
Organic or natural weed killers
Many organic weed killers use more “natural” ingredients such as vinegar, neem oil, or citric acid in place of harsher chemicals. Even boiling water can work!
They’re much slower and slightly less effective, but are safer to use – especially if you have pets.
There are also natural, manual weed-killing methods such as smothering with cut-up garbage bags, landscape fabric, or mulch.
How to Choose a Weed Killer
There are quite a few factors that go into choosing the right weed killer for your lawn.
The important part is, of course, that the product will kill weeds – but you’ll need to consider more than that!
Weed needs
Start by identifying the problem in your lawn. Do you have a full-on invasion, or are there just a few unwanted guests popping up in a corner?
Additionally, what type(s) of weed is taking over? Is it clover, oxalis, or the dreaded bindii?
You’ll need to understand these factors so you can choose the appropriate weed killer (or herbicide). Many products are formulated to kill specific types of weeds or ignore beneficial plants.
Application
Most weed killers come ready-to-use or as a concentrate that you dilute with water. Ready-to-use (RTU) products come in their own spray bottles, while concentrates will need to be mixed in a separate container.
For concentrates, you’ll need to decide if you’ll use a hand sprayer for targeted application (individual weeds) or a pressure sprayer for broad application (large areas).
Other weed killers come in a granular formula that you can spread across the lawn.
Active ingredient
Most chemical-based weed killers use potent ingredients like glyphosate or dicamba. These products act very fast and are very thorough, but can be damaging to the ground and the surrounding environment in the long run.
The chemicals are also very toxic to humans and pets, and may even kill off beneficial plants. Evaluate the ingredients in any product before making a purchase.
If you’d prefer more organic ingredients, look for products that contain vinegar, citric acid, or soaps. They’ll be much slower, but are generally “safer.”
Targeted plants
Non-selective herbicides can act very fast and thoroughly, but because they’re “non-selective,” they can kill even beneficial or desirable plants – including your lawn grass.
A selective herbicide, on the other hand, contains ingredients that target specific plant life. It’ll generally only target weeds and leave grass alone, but always check the ingredients!
Certain selective weed killers also target broadleaf grasses, which include buffalo lawns.
Environmental impact
Any responsible homeowner should think about the impact of the weed killer beyond their lawn.
Consider whether the chemicals might leach into the groundwater or reach any nearby water sources through runoff. Could weather carry herbicide through spray drift, affecting nearby wildlife?
You may need to check your local council regulations on what herbicides they allow for residential use.
Coverage
Ready-to-use herbicides often come in limited amounts – typically a litre or less, since they come in spray bottles that you have to carry around. This means an RTU weed killer may not cover large areas of your lawn.
Some RTU herbicides come in larger volumes, but must be transferred to a tank or attached to a sprayer.
Concentrates, meanwhile, might offer more coverage since you’ll be diluting the product with water. That gives you more product to use over more space.
Weather resistance
It’s typically best practice to apply any weed killer on a clear day with no wind or chance of rain. This gives the product the best chance of penetrating the ground and doing its work.
It also minimises the risk of product drift, when wind or rain carries off the weed killer where it can harm plants and animals other than the intended targets.
However, while we can control weeds (to an extent), we can’t control the weather! Some herbicides offer levels of rain resistance or weather resistance, meaning they’re not easily washed away.
Best Weed Killer Australia by Type
Need to tackle even tough weeds on your lawn?
We’ve rounded up our top picks for the best weed killer Australia.
Best Overall Weed Killer Australia: Yates Zero Ultra Tough RTU Weedkiller
Yates offers many high-quality gardening and lawn care products, and their Zero Ultra Tough RTU Weedkiller is no exception.
This heavy-duty product permanently kills off even tough weeds, down to the roots – including bamboo, onion weed, and more. It’s also rainproof within 30 minutes!
This non-selective product is easily applied thanks to its sprayer, so you can easily use it along paths, driveways, and fence lines. Moreover, it contains Vanishing Blue Highlighter so you know where you’ve already worked.
One downside, though, is it’s only 750ml – so you’ll need more than one bottle for a large invasion or larger lawns.
Best Selective Weed Killer Australia: SureFire Dicamba M Selective Herbicide
This Australian-made product is perfect for most Aussie lawns (except for buffalo grass)! SureFire advertises the Dicamba M Selective Herbicide as low-toxicity but high effectiveness.
Most reviewers highlight how easy it is to use and how one bottle can cover a large area. It targets most broadleaf weeds, but is less effective against woody weeds.
Once you’ve applied it, though, you can expect a (mostly) weed-free lawn within 2 weeks!
Best Non-Selective Weed Killer Australia: Roundup Natural Weed Killer
This Roundup’s version of non-glyphosate weed killers. Its natural active ingredient is 18.3g/L nonanoic acid, which kills almost all weeds on contact.
Thanks to Roundup’s potent formula and “advanced weedkilling technology,” the Natural Weed Killer will produce results within 12 hours of application. It kills any plants down to the root – so be careful with application, since that could include plants you do want!
Roundup Natural Weed Killer works through direct contact, as it’s absorbed through leaves then enters the plant’s sap stream. This means you can also use it on moss and possibly algae as well.
Best Pre-Emergent Herbicide Australia: Miracle-Gro SnF+Weed Preventer
If you want to stop weeds before they get started, pick up some Miracle-Gro SnF+Weed Preventer!
This pre-emergent herbicide both prevents weeds from growing and feeds your lawn for up to 3 months. One bottle can cover 12sqm at minimum.
The SnF+Weed Preventer is extremely easy to use, since “SnF” stands for “Shake and Feed.” As the name suggests, shake up the product then sprinkle the powder onto your lawn.
Apply the product before the growing season for maximum weed prevention.
Best Organic Weed Killer Australia: Slasher Organic Ready-to-Use Weed Killer
Slasher’s Organic Weed Killer is certified glyphosate-free and is 100% biodegradable. Its active ingredient is nonanoic acid (or pelargonic acid), a plant-derived compound.
It’s non-selective, and works on everything from standard weeds to algae and lichen on contact. It also works very quickly, and can leave your lawn weed-free within 2 weeks.
The formula doesn’t need water or heat to activate, so you can use it anywhere – even around edible gardens. As it’s it’s approved for organic gardening – so it’s also the best weed killer for garden beds in Australia.
Best Weed Killer Concentrate Australia: Roundup Advance Concentrate
Get more bang for your buck by picking a weedkiller concentrate! One bottle of Roundup’s Advance Concentrate Weedkiller can treat up to 280sqm – more than an entire tennis court.
This weed killer becomes rainproof within 2 hours and is non-residual, so it’s not active in the soil after it dries. You can plant again after just 7 days.
The powerful formula is suitable for use even around waterways.
Best Weed and Feed Combo Australia: Preen Garden Weed Preventer Plus Plant Food
Get a one-two punch with the Preen Garden Weed Preventer Plus Plant Food – it both prevents those unwanted plants and feeds the grass in one go.
Preen’s weed and fertiliser combo can tackle all sorts of grassy weeds, from crabgrass to knotweed. And thanks to its balanced fertiliser formula, it’s safe to use around fruits, vegetables, and even nut trees!
Preen Garden Weed Preventer Plus Plant Food is best for large lawns and gardens, since one 7.26kg bottle can cover up to 230sqm. One application equals three months of coverage.
Check out our blog post on the best time to weed and feed in order to use your product at the correct times of year.
Best Natural Weed Killer Australia: Vinegar, salt, and dish soap
If you prefer a more natural solution to weeds, there are several DIY weed killers!
One common recipe for homemade weed killer involves mixing 1 tablespoon of dish soap into 3 litres of white vinegar or horticultural vinegar.
For white vinegar, you can opt to add a cup of salt to make the solution more potent and effective. However, salt can alter the ground pH, so be careful when applying.
Fill a spray bottle or garden sprayer with the mixture. Then carefully apply it to the affected area, ensuring it thoroughly coats the weeds.
NOTE: Vinegar is a non-selective weed killer and it has no residual action, so it will not kill off any roots or seeds underground. It’s also not good for long-term management, since it can affect the pH and nutrients in the ground.
Best Weed Suppressant Australia: Corn gluten meal
Check your local garden centre or agricultural shop to see if they carry this. Corn gluten meal is the product left over after corn is milled.
It’s a common weed suppressor, and is particularly effective at controlling crabgrass and clover. However, as it’s non-selective, it’s best applied after the growing season or when you’re not overseeding.
Spread 1kg of corn gluten meal per 10sqm, then water well. Let the corn gluten meal dry naturally.
Best Weed Killers in Australia for Different Uses
Maybe you’re looking for a weed killer that’s suitable for a specific use – such as one that won’t kill grass, or one that works on garden beds.
Here are our picks for the best weed killers based on use.
Best Weed Killer for Lawns Australia: Scotts Lawn Builder
If you’re looking for the best weed killer that won’t kill grass in Australia, go for Scotts Lawn Builder.
This product works on almost any type of lawn – including couch, kikuyu, and buffalo grass. As Scotts says – it “kills weeds, not lawns.”
That makes Scotts Lawn Builder the best weed killer for buffalo grass in Australia as well.
Best of all, thanks to its Weed, Feed, & Green up formula, you’re actively feeding the grasses while killing the unwanted plants.
And the product has low phosphorus content (0.7%), so it’s safe to use on any Australian lawn without risk to ground or surface water.
The 2L bottle comes with an easy sprayer for efficient application, and can cover up to 130sqm.
Best Path Weed Killer Australia: Roundup Fast-Action Rainproof and Non-Residual Weed Killer with Easy-Grip
Roundup’s Fast-Action Weed Killer with Easy Grip is perfect for controlling weeds around paths, driveways, and fences.
It’s non-residual in the soil, and is rainproof after just 30 minutes – so no need to worry about the weather.
Moreover, the accompanying precision sprayer means you can target just the weeds inside or along your path without harming the rest of your yard.
Best Path Weed Killer Australia: Roundup Fast-Action Rainproof and Non-Residual Weed Killer with Easy-Grip
Roundup’s Fast-Action Weed Killer with Easy Grip is perfect for controlling weeds around paths, driveways, and fences.
It’s non-residual in the soil, and is rainproof after just 30 minutes – so no need to worry about the weather.
Moreover, the accompanying precision sprayer means you can target just the weeds inside or along your path without harming the rest of your yard.
Best Weed Killer for Broadleaf Weeds Australia: SureFire Buffalo Bindi and Broadleaf Weed Killer
SureFire’s product is one of the best broadleaf weed killers you can get. It uses bromoxynil (a nitrile herbicide) and MCPA to control any broadleaf weeds in your yard – so it’s your best bindi killer, alongside clover, oxalis, and thistles..
You can use SureFire Buffalo Bindi and Broadleaf Weed Killer on many Aussie grasses, including kikuyu, couch, Queensland, and even buffalo grass.
The product comes as a concentrate, so you’ll need to dilute it and mix it in a sprayer for application.
Best Weed Killer for Poison Ivy Australia: Roundup Poison Ivy Plus Ready-to-Use Wand Sprayer
If you’ve got a problem with poison ivy, poison oak, or poison sumac – this is the product for you.
Roundup’s Poison Ivy Plus RTU Sprayer is specially formulated with 2 brush-killing ingredients to penetrate even waxy leaves on plants.
The sprayer allows you to target even vines that are growing up fences, posts, and mature trunks. For shrubs and younger trees, cut back the weeds and apply Roundup on the regrowth.
Best Pet-Friendly Weed Killer Australia: Natural Armor 30% Home & Garden Vinegar
Unlike other products, Natural Armor’s 30% Home & Garden Vinegar uses all-natural ingredients – primarily 30% acetic acid.
That’s six times stronger than regular household vinegar, making it extremely potent and effective and controlling weeds in your yard.
Natural Armor’s environmentally-friendly formula is safe for use around pets, although you’ll still need to ensure they’re kept away during and immediately after application.
Best Tools for Weed Killers in Australia
Besides any of the above products, you can add these tools to your weed-fighting arsenal.
Best Hand Weeder Australia: Spear & Jackson Garden Hand Weeder
If you only have a small weed problem, the Spear & Jackson Garden Hand Weeder is a great tool to get rid of weeds while giving yourself a workout.
It’s got a soft and ergonomic handle with a thumb grip for additional control. The blade is made of 1.4mm carbon steel, with an attached finger guard for safety.
This hand weeder lets you easily tackle smaller plants in lawns and raised beds.
Best Manual Weed Puller Australia: Hoselink Stand-Up Weed Puller
No need to break your back while weeding! Hoselink’s Stand-Up Weed Puller features a lightweight design with an easy-grip handle so you can uproot unwanted plants without bending over.
The stainless steel claws will dig deep into the ground and fully uproot any unwanted plant. Then just use the built-in ejection system to release the weed – letting you stay fully upright while working.
It’s very easy to clean the Stand-Up Weed Puller (and you should clean it to prevent dirt build-up). Then simply store it away for the next time.
Best Weed Wand Australia: Craftsman Battery-Powered Sprayer Wand
A weed wand is a tool used to spray weed killer or any other liquid products onto your lawn. You simply fit it onto the product bottle, then point and spray – no pumping needed!
Craftsman’s Battery-Powered sprayer can spray up to 6 metres on up to 60 minutes of continuous use. It needs 4 AA batteries to use (and is compatible with rechargeable ones).
This sprayer wand works on any 38mm bottle.
Best Pressure Sprayer Australia: Gardena Pressure Sprayer 5L
If you’ve got a large yard or you want to cover more ground in one go, invest in a pressure sprayer!
This 5-litre sprayer is perfect for applying weed killer, watering plants, or even applying fertiliser. Just pump the D-handle to build up pressure, and don’t worry – the foot treads will keep it firmly in place.
Need to walk around? No problem. Gardena has incorporated a comfortable shoulder strap for easy carrying. Plus, there’s a viewing strip so you can see how much liquid is left in the tank.
How to Use Weed Killers
Check the weather ahead of time to ensure it won’t be windy or rainy for a few days. This will ensure the product doesn’t spread or get washed out.
Do not apply weed killer right after you’ve mowed the lawn as this could cause extra stress. It’s also best not to apply any weed killer on newly watered ground.
Follow all the instructions on the product label, whether that’s diluting the product, using a wetting agent, or applying it directly to the lawn.
Check the wind before spraying so you don’t cause any product drift.
Always wear protective equipment when working. That includes rubber gloves, long pants, closed shoes, a face mask or respirator, and eye protection.
Do not water your lawn for a few days. Keep pets and children away from the area as well.
Keep an eye on your yard to check effectiveness or watch for any damage. You may need to apply your weed killer more than once to get rid of all the weeds.
Precautions When Using Weed Killers
There are some concerns about products that use a potent ingredient called glyphosate. Some research has brought up its potentially harmful impact on the environment and health risks for users.
Always make sure you follow the guidelines when using chemical herbicides, and check your local council regulations about allowable products.
Avoid using any products that contain bleach, since it can drastically affect your soil and plant health.
Check the ingredients and label of any weed killer before purchase – many products are toxic to pets (especially dogs). Either apply products when you can ensure your pet’s absence, or choose a pet-friendly alternative.
You should also check the ingredients before applying any herbicide to garden beds with crops. Some products are not safe for use around edible plants, as they could be absorbed through the roots.
Lawn Care Tips for Weed Prevention
The best way to prevent weeds is proper lawn maintenance. A healthy and happy lawn is more resistant to weeds, pests, and disease.
Mow the grass regularly – a good rule for how often to mow in Australia is every 2 weeks in the summer, and every 3–5 weeks in autumn and winter (if at all).
Do not cut more than 1/3 of the height of the grass to keep it healthy.
Aerate your lawn once a year to prevent soil compaction and let the ground “breathe.” It also helps the grass roots better absorb water and nutrients.
Lawn thatch is good in moderation, but too much can smother your grass and lead to a dead lawn. If the build-up is reaching 2cm, it’s a good time to dethatch your lawn.
Properly fertilise your lawn to maintain a good nutrient balance and avoid fertiliser burn. Alternatively, you can top-dress your lawn, or use mulch or compost.
