The best weed killers do one thing, and one thing only: kill your garden weeds. This might seem obvious, but it’s harder than you think to develop a weed-killing product that destroys weeds on a pathway without polishing off the plants in your borders, or that can remove dandelions and creeping thistle from your lawn without turning your green grass brown.
Luckily, today’s top weed killers are up to the job, and they’re a whole lot easier on the garden – and on the local wildlife – than some of the more brutal options gardeners used to employ. What’s more, they don’t have to cost the Earth, either literally or figuratively.
Chemical weed killers basically break down into five main types, and which you pick depends on the weeds you’re trying to get rid of, and the position that you find those weeds in.
Systemic weed killers: Systemic weed killers are usually taken in through the foliage, and from there spread through the rest of the plant to its roots. This gives the weed killer a decent fighting chance of killing off the whole plant. They usually take longer to act, but are effective against the plants they’re designed to kill. What’s more, they don’t hang around in the soil afterward, which means it’s safe to plant again.
Contact weed killers: These powerful herbicides destroy plant life, killing any part they touch or – in some cases – the whole plant as they’re absorbed. Again, they take a while to work – sometimes weeks – but afterward, they’re neutralised by the soil.
Non-selective weed killers: These ultra-violent weed killers tend to be fast and effective, but they destroy just about anything they come into contact with, affecting both the plants and soil. That means they’re a little too effective to be used in lawns, beds or borders in most cases, and are best used on driveway and patio weeds.
Selective weed killers: These more discriminating herbicides kill only a specific plant or type of plant. For instance, they might tackle lawn weeds like clover or dandelions while leaving your grass alone. Most lawn weed killers are selective.
Residual weed killers: These weed killers target the soil and kill weeds as they’re absorbed through the roots. They’re effective and long-lasting, but their awesome power comes at a price, hanging around in your garden and affecting the soil quality and future plant growth.
In general, you should avoid using non-selective or residual weed killers anywhere except pathways and driveways, if you have to use them at all. Contact and systemic weed killers are safer as long as they’re applied carefully, while selective weed killers are the best bet for troublesome beds and borders or your lawn.
Check the instructions. If you’re using a ready-made spray you can put on some gloves and get to work, and, if it’s a concentrate, pour it into a watering can or sprayer and dilute your mixture as directed on the bottle.
Check the forecast to avoid a downpour washing your weed killer away, or high winds that might blow the mixture back in your face. It’s also worth applying weed killer in the morning, as this gives the unwanted plants plenty of time to absorb the solution, and get busy dying.
Some weed killers start to work within 24 hours, while others might take a week to have much impact. Don’t be tempted to reapply without reading the instructions. If, after the quoted time, you still have persistent weeds hanging in there, there’s usually no harm in giving them another dose to finish them off.
Chemical weed killers aren’t always the answer, and you could try more natural solutions like boiling water or white vinegar/acetic acid (which, while Defra approved, isn’t actually considered organic). A good hoe can be effective in beds and borders, while there are various implements for digging weeds out of lawns, paths and driveways. Best of all, you can buy a flame weeder or flame gun. It’s not exactly eco-friendly and needs to be taken seriously, but it does make you feel a bit like a 1980s action hero when you’re taking out the weeds along the garden path.
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Price: £17 | Buy now from Amazon
Resolva’s Ready to Use Weedkiller promises to serve up visible results just 24 hours after deployment. The biodegradable formula ensures that this weed killer won't linger around in the soil any longer than needed, and it will kill the weed at the root for lasting results.
It’s cheap and effective, and if you plump for the three-litre version, you will have enough to treat 120m². The five-litre version comes with a handy pump and an adjustable spray for targeted weed killing.
Key specs – Type: Selective; Volume: 3-5 litres; Deployment method: Spray; Visible results in: 24 hours
Price: £30 | Buy now from Amazon
Roundup’s Path and Drive Pump N Go Weedkiller does exactly what it says on the package. Designed specifically to target the sorts of weeds that sprout through paths, patios and gravel driveways, the pressure sprayer destroys weeds in one to two days.
Five litres will cover a generous 150m² area, and refills are available to purchase online if you’ve got a particularly large garden.
Key specs – Type: Contact/non-selective; Volume: 5 litres; Deployment method: Pump and spray; Visible results in: 1-2 days
Price: £26 | Buy now from Amazon
Not to be confused with the path-specific option above, Roundup’s Total Weedkiller is a popular do-it-all weed killer. This is the all-encompassing sister product to the Path & Drive option above, and it will kill most garden weeds after a single application, with visible results showing in one to two days.
It leaves no harmful residue and it’s very easy to deploy. It should kill the weeds in your garden and their roots, before degrading in the soil without leaving any damaging substances in its wake.
Key specs – Type: Contact/non-selective; Volume: 5 litres; Deployment method: Pump and spray; Visible results in: 1-2 days
Price: £9 (750ml spray) | Buy now from Keen Gardener
Weedfree Plus is another good all-rounder that you can buy as a ready-to-spray 750ml trigger bottle or as a 510ml or 1.2l concentrate. Spray it on most weeds and grasses and they will be curling up and looking sickly within the first day, as it goes to work on the foliage before busting up the roots. It’s based on Pelargonic acid and Maleic Hydrazide (a growth regulator), and while you will need to respray to keep heavier weeds under control, it’s effective and biodegrades naturally in the soil.
Its real strength, though, is that it can control weeds that other weed killers tend to struggle with, including horsetail/mare’s tail and ground elder, as it did on an overgrown bank and a disused veg bed where other weed killers had failed miserably. It’s a good bet if you need a powerful weed killer but you don’t want to spray something really nasty on your plot.
Key specs – Type: Contact/non-selective; Volume: 510ml; Deployment method: None provided; Visible results in: 1 day
Buy now from Keen Gardener
Price: £24 | Buy now from B&Q
Recent health scares over Glyphosate-based weed killers have sent a lot of people looking for more natural products, some of which are excellent, some of which are ineffective or hugely overpriced. Roundup Naturals is one of the better options. It’s not the most organic or eco-conscious option, but it’s based on 100% natural ingredients and it’s powerful enough to get weeds wilting within three hours of application. It then breaks down in the soil within three days of use, leaving you free to replant.
We found it worked well on pathways, cracked driveways, borders and overgrown banks, though you might need a second application on some hard-to-shift ground weeds. If you worry about what you’re spraying on your garden, give this one a try.
Key specs – Type: Contact/non-selective; Volume: 3l; Deployment method: Pump and spray; Visible results in: 3 hours
Buy now from B&Q
Price: £15 | Buy now from Amazon
EverGreen’s Complete Lawn Food, Weed and Moss Killer is a great addition to the lazy gardener’s arsenal. This catch-all product kills weeds and controls moss while feeding your lawn thanks to a blend of ingredients including nutrients such as nitrogen and potassium.
It comes in granule form rather than a liquid and can be sprinkled over your lawn by hand, although bear in mind that you will need to measure amounts precisely to ensure an even spread. A spreader tool is recommended for easy application. A controlled release of nitrogen means your lawn will still benefit up to six weeks after the initial treatment.
Key specs – Type: Selective; Weight: 7kg; Deployment method: None provided; Visible results in: 7 days
Price: £20 | Buy now from Amazon
Weedol’s Lawn Weedkiller targets the kind of weeds that spring up around your grassy garden area (dandelions, daisies, clover and so on), without compromising the integrity and lushness of the lawn itself.
Although it doesn’t come with its own method of deployment, this concentrated weed killer is easily diluted with water and applied with any watering can or spray tool at your disposal.
Key specs – Type: Contact/selective; Volume: 1 litre (undiluted); Deployment method: None provided; Visible results in: Not specified
Price: £24 | Buy now from Amazon
If the weeds in your garden are proving too big and tough for traditional weed killers, Vitax SBK’s Brushwood Killer Tough Weedkiller is the one to pick. This heavy-duty option targets brambles, nettles, dock, woody weeds, hardwood saplings and tree stumps. And despite the enhanced strength of this weed killer, it won’t kill grass, meaning you can rid your garden of heavy weed threats without endangering your lawn.
Just make sure to wear gloves when using it – this isn’t a weed killer you want on your skin.
Key specs – Type: Selective; Volume: 1 litre (undiluted); Deployment method: None provided; Visible results in: Not specified
Price: £4 | Buy now from Wilko
Moss can be tricky to remove from pathways, patios and brickwork, particularly in shady areas where it often runs rampant. If you’re not able to pressure wash the moss away, Wilko’s Moss Control is a great option. The easy to use spray bottle emits a fine mist that doesn’t drip onto your trigger finger, and there’s an on/off lock to ensure no leaks when not in use.
It works really quickly too: within a few hours of spraying mossy patches along bricks and concrete we could see the difference. There’s a pretty strong vinegary smell, so we’d wear gloves and apply sparingly. The one litre spray bottle should suffice for 35 square metres, making it a bargain at the price.
Key specs – Type: Contact/non-selective; Volume: 1 litre; Deployment method: Spray; Visible results in: a few hours
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