10 Best Weed Killers | Australian Buying Guide 2022

Different Types of Weed Killer

These are the two main types of weed killer:

Pre-Emergent Weed Killer

This is for killing weeds before they start to grow, preventing seeds from growing by stunting root growth in the very early stages of germination.

Pre-emergent herbicides should be used in very early spring to be effective, as they won’t harm plants that already have an established root system. 

This means it’s safe for your lawn and flower beds, but shouldn’t be used near any other new seeds.

Post-Emergent Weed Killer

A post-emergent herbicide is one that kills established, growing weeds. This will only be effective on weeds you can already see.

You can use them any time of year, but be careful not to let the spray or granules come into contact with your lawn or established plants, as it will kill them too.

Weed killers are also categorised by how they work:

Contact Weed Killer 

This will kill off any plant it comes into physical contact with, wilting and killing weeds very quickly. You’ll usually start to see results within an hour or so. 

They tend to destroy the foliage of the weeds without affecting the root system. This can kill lighter weed growth, but usually means reapplying the weed killer several times to properly kill more established weeds. 

Contact weed killer should be used on annual weeds that spread via seeds.

Systemic Weed Killer 

These weed killers work by being absorbed by the leaves of the plant and entering the root system, stopping the plant’s ability to get nutrients from the soil. They work more slowly, and you’ll see results in 1-3 weeks. 

This is highly effective on perennial weeds that spread through seeds and the soil. Some weed killers are both systemic and contact, and these will usually be marked as general-purpose or all-rounder weed killers.

What are the Best Weed Killers for Lawns?

There are several options for killing weeds in lawn:

• Manual – Manually digging out weeds by hand, using a fork or cultivator.
  (Should you decide to go for the latter, see our cultivator product reviews and buying guide.) 
• Pre-emergent weed killer – This will kill weeds before they start growing without affecting established plants and grass. However, it will affect newly sown grass seed.
• Post-emergent weed killer – Although this will kill the grass as well as the weeds, it’s a good option if your lawn is overgrown with weeds and you want to replant that section.

Why is a  the best option for weeds in your pavement?

The reason why I recommend using a weed killer to control the weeds in your paved area’s is actually different to why it is useful on large scale gardens.

Simply put, weeds can have very strong root systems and generally speaking, when you try and remove weeds from between pavers, the roots often break off. If you don’t remove the root system, often the weeds can simply just grow back. 

The weed killers reviewed below not only kill the root system but will also make it easier to pull the whole weed out after the weed has died.

How Do You Stop Weeds from Coming Back?

This is a gardener’s biggest challenge! Unfortunately, weeds continually get into our gardens from passing birds and wildlife, blown in from other gardens, or even on the soles of our shoes. Luckily, there are some things you can do:

• Keep your existing weeds under control with a post-emergent weed killer
• Use a pre-emergent weed killer in the very early spring before weeds start growing
• Pull out any weeds you do see, especially if they are seeding. Be very careful and dispose of them in your garbage, not your compost.
• Boost your garden’s health by planting native plants, mulching your lawn and flowerbeds, and feeding your plants with the right fertiliser.
  
  The stronger your existing plants are, the harder weeds will have to work to establish themselves.

How to Use Weed Killer Without Harming Wildlife

Some weed killers are very harmful to native ecosystems, wildlife and human health, especially those that are high in glyphosates. If you do need to use a strong glyphosate weed killer, be careful to use it sparingly and avoid pollination times in spring and summer, as this can kill bees and other beneficial insects.

Organic, Pet/Child Safe and Natural Weed Killers

If you have children and pets or are concerned about the natural environment (as we all should be), we recommend that you use a weed killer that is pet safe, child safe, and organic.

In addition to buying these weed killers, you can also try these safe weed removal methods:

• Physical removal – This is the safest but most physically-demanding way of removing weeds. If you don’t have many weeds, and you don’t have back pain, this is a good option. Use a small garden fork to dig down and remove the entire weed with the roots.
  
  Try to spend time doing manual weeding in early spring before the weeds develop seed heads and remember to wear sun protection. It can also help to work when the ground is damp.
• Boiling water – You can effectively kill any type of weed or plant by pouring boiling water onto them. It’s completely safe for the environment, kids, and pets too, as long as you keep them away from where you are pouring and remember to protect your hands too!
• Salt – Sprinkling weeds with salt or adding salt to boiling water will quickly kill weeds, and it’s great for clearing paving or driveways.
  
  If you plan to sow new seed or grow new plants in these areas, just flush it with clean water before you plant to clear out the excess salt.
• 5% vinegar – Vinegar that has an acetic acid level of 5% or more is a key ingredient in natural, organic weed killers. All you need to do is spray it onto the plant (a second dose may be required), and the weed should start to die quite quickly. 
• Cornmeal – The gluten in cornmeal is a pre-emergent organic herbicide that works on pre-emergent weeds. You can spread it out over your lawn or flowerbeds in early spring.

How to Apply Weed Killer

When using a weed killer, always follow the manufacturer’s instructions. Don’t be tempted to make the solution stronger if you have to mix it yourself, as this doesn’t make it more effective.

Always apply the weed killer on a dry day when rain is not expected for around 48 hours.

Be sure to wear protective coverings over your eyes, mouth and hands, and to remove pets and children from the area for the entire waiting period (usually a few hours) as specified by the manufacturer.

Use a weed or garden sprayer - read our article on what to look for in a good sprayer and our reviews here

1.  Roundup Regular 24H Weed Killer Spray

There’s a good reason that roundup is the market leader in weed killers; they’re the best. Roundup has a massive range of products online, and all work well at their jobs, but good old-fashioned roundup regular should be a go-to weed killer for any gardener.

OK, so it’s not organic, but no weed killers are (none that work anyway).

Glyphosate is a horrible chemical. It stinks, it’s bad for your garden, and awful for wildlife, but if you use it responsibly on hot days, and don’t spray anywhere where wildlife will get to it before it dries up, it’s safe.

So use Roundup responsibly, and target it right at the leaves of the plants you want to get rid of. The only weed it won’t kill is marestail, the prehistoric pest plant that just won’t die! 

However, it does help to weaken marestail as part of a regular routine that involves spraying, then pulling, then bruising the plant. 

2. Tuffweed 360 Aquatic Glyphosate Weed Killer 

While glyphosate is incredibly toxic to wildlife, its effects wear off once it's dry, but continue to poison the roots of plants. Tuffweed is pure glyphosate, so smells awful, and can kill any plant it touches, but needs to be used with extreme caution. 

But, if you’re at your wits end with tough weeds like bindii or marestail, then this is a good last resort and is pretty much guaranteed to end your problem within 2-3 years of repeat application for even the worst deep-rooted weeds.

3. HOT Devil Super Weed Killer

When in doubt, kill it with fire. There is no weed in the garden that can survive being burned to its roots, so if you don’t like the idea of chemical weed killers, get a weed burner.

They need a little bit of practice, and patience is very much a virtue as the aim is to get right to the roots, and not just burn the foliage of weeds.

Some weeds, like marestail and bindii, will still regrow the following year, but they will be weaker, and fail to seed around. Regular burning prevents photosynthesis and the weeds will eventually just die.

For a wildlife-friendly approach, fire might not sound ideal, but it’s far safer in the long term as it doesn’t release any chemical pesticides or herbicides into the garden.

4. Lawn Builder Weed, Feed and Green Up

Lawn Builder specialise in lawn care products, so their 3in1 weed killer is ideal for gardeners who want that extra peace of mind when trying to remove tough weeds without harming their grass.

Like all weed killers, no matter their ingredients, it’s toxic and should be used sparingly and responsibly, but it’s an effective substitute for more potent general weed killers.

5. Richgro Beat A Weed Natural Weedkiller

This all-natural weed killer is a great choice for eco-friendly gardening, or if you have children and pets. It comes in a ready-to-use spray bottle, and can kill weeds, moss, and algae.

Tougher, more established weeds may need a second dose to completely kill them off.

6. Yates Zero Bindii Clover Weeder

This is a broadleaf-specific weed killer for removing dandelions, clover, and bindii. By combining two types of weed killer, it’s effective on a wide range of weed types, and it’s very economical, with 500ml treating 330 square meters. As a systemic weed killer, it shows results within 4 weeks.

7. Dicamba M Selective Herbicide Weed Killer

This is a great weed killer for killing broadleaf weeds like bindii and clover, and it can be used safely on your lawn without killing your grass.

It’s low toxicity but still effective, and one litre can treat an impressive 1500 square metres.

8. Richgro Tree, Blackberry and Woody Weed Killer

Woody weeds need specialist treatment. They can be deep-rooted and are very resistant to most foliar weed killers. 

Richgro’s Tree & blackberry weed killer focuses its energy on keeping right down to the roots of woody plants and is best used by painting it directly onto cut stems.

Stop digging roots out when there will be more to come, and attack the entire system with targeted action from Richgro.

9. NEW Weedout - No Glyphosate, Natural Organic WeedKiller

This organic, glyphosate-free weed killer is a great way to get rid of unwanted weeds in paving, flowerbeds, vegetable gardens and lawns without harming the environment.

Australian-made, it uses acetic acid and salt to deliver fast results, especially when applied on hot, sunny days. Wilting will usually occur within a couple of hours.

10. Brunnings Extra Strength Feed 'n Weed

If you like Brunnings Feed ‘n Weed but want something with a bit more power in a liquid form, this is a great option. It’s a selective weed killer that’s safe for most lawn types, killing off broadleaf weeds like clover, bindii, and dandelions without harming your grass.

The fertiliser component helps to nourish your lawn and boost growth, making it harder for weeds to grow.

Roundup Regular was always going to get our best weedkiller spot. It’s fast-acting and long-lasting and has been the world’s favourite weed killer brand for decades.

The spray bottle for the 3-litre option is a little heavy to carry, but it comes in different sizes. However, it’s worth noting that the larger tubs last longer, and are significantly better value than the 1 or 1.5-litre bottles.

If you’re sensible, responsible, and watchful, glyphosate can be used safely in the garden, with near immediate visible effects on weeds. While there are some weeds that can resist and return from deep roots the following year, a repeated application will put an end to them.

Tuffweed is one of the few pure glyphosate weed killers on the market, and its price is definitely reflective of that, but well worth it if you’ve tried everything else.

The HOT Devil weed killer is a simple propane tank attached to a burner rod. There’s nothing particularly fancy about it, but it's purpose-built to make weed killing an easy task, and the bottles are interchangeable with most propane bottles from any DIY store.

Once the tank runs dry, just buy a budget replacement and you’re all set again.