Best weed killer UK: which one to buy, job by job

There is no best weed killer, which is why no two lists agree. There are six jobs, and buying for the wrong job is the real reason most people decide a bottle failed them. So this is the decision rather than a ranking: name the job, get the chemistry that does it, get the catch that comes with it, and get sent to the resource that works it through properly.

By The Weed GuyLast updated 23 September 2026

The short version

Choose the job first, the format second, and the brand will turn out not to matter. A ready-to-use trigger bottle is single digits: Roundup Fast Action is 7.2 grams of glyphosate a litre, Resolva 24H is 8.39. The concentrate on the shelf above it is 360. Same active ingredient, same aisle, and the format did all of that on its own.

Name the job, and the aisle shrinks to one bottle

Read down the first column until you recognise your own garden, then read across. The last column is where each answer is taken apart properly, because none of these decisions fits in a table cell.

The job you have got	What actually does it	The catch that comes with it	Worked through on
A few weeds in a path, a crack or along a border edge	A ready-to-use glyphosate trigger bottle. It is systemic, so it travels down to the root instead of scorching the top.	You are paying to have water shipped to you. Sensible for a dozen weeds, hopeless for a drive.	concentrate against ready to use
A whole drive, path or patio in one go	An amateur glyphosate concentrate and a pump sprayer. The top of the amateur range is 360 g/L and it needs no paperwork at all.	The saving only exists if you measure it. Mixing by eye is how people end up calling a strong bottle weak.	label rates scaled to a 5 or 15 litre tank
Ground that has to stay bare for months, not weeks	A residual, which on the amateur register means diflufenican paired with glyphosate. Glyphosate on its own leaves nothing behind to stop the next seed.	All four amateur residual products are approved for permeable ground over soil, and barred from concrete, tarmac and paved areas.	what the residual half of a path and drive bottle does
Brambles, ivy, a cut stump or anything woody	Triclopyr. It works by imitating a growth hormone, not by being a stronger version of glyphosate.	It leaves grass standing. Useful in rough ground, a nuisance in a border you wanted cleared.	triclopyr and the two SBK bottles
A garden a dog or a cat actually uses	There is no such purchase. Britain has no pet safe classification to buy against, so the decision moves to the re-entry line on the label in front of you.	At concentrate strength it is the natural bottles carrying the hazard pictogram, not the glyphosate ones.	what the pet safe wording is actually worth
It has to look dead by this evening	A contact acid, pelargonic or acetic. Fast, visible and shallow.	It destroys the leaf and never reaches the root, so what you have bought is a fortnight.	what the natural and homemade options really do
You know what you want and just need somewhere to buy it	Price it by the gram of active ingredient rather than by the bottle, then buy wherever that lands.	The two trade counters people search for hardest carry the least glyphosate of anywhere on the high street.	what each shop actually stocks

Notice what is missing from that table. Not one row turns on a brand name.

Buying weed killer is four decisions, and only one of them is the chemical

The job comes first, because it fixes the chemistry. The format comes second, because it fixes the dose and the cost. The surface comes third, because it decides what the label will actually let you do. The brand comes fourth, and by then there is almost nothing left for it to change.

That last point is worth putting a number on. Of the herbicides approved for amateur use in Great Britain, 133 are glyphosate products. They are the same active substance in different bottles at different concentrations, so ranking them against one another is the least informative thing anyone can do with that shelf, and it is exactly what a best weed killer list does.

Format, on the other hand, moves the number enormously. A trigger bottle sits at 7.2 or 8.39 grams of glyphosate a litre because it has already been diluted for you. A concentrate of the same active reaches 360 in the bottle. One decision, and a fiftyfold spread in what you are carrying home. Which of the two is right for you is a question of the area you have to cover and whether you will measure, and I have taken that decision apart on the concentrate versus ready-to-use resource.

Which leaves brand as a tie-breaker rather than a decision, and even then the range inside one brand varies far more than the gap between brands. If you have already settled on a name, the registered concentrations behind the Roundup range are set out product by product, and the same is done for the amateur and professional Gallup tiers and for Doff. Read those to find out what is in a bottle, not to pick a side.

Two questions eliminate almost everything in the aisle

This is the whole decision compressed. Answer both, and there is one sensible purchase left standing.

Question one: does it have to reach the root? A systemic product is absorbed by the leaf and carried through the plant, so the root dies with the top. A contact product stays on the outside of the plant and wrecks whatever the droplets touched. A week-old seedling dies to either. Anything with a root store, which is most of what annoys you, only dies to a systemic, and no amount of extra strength turns a contact product into one.

Question two: does it have to stop the next one? Nothing glyphosate touches stays in the soil afterwards. It deals with the plants standing there on the day and has no effect whatsoever on the ones that germinate once you have packed the sprayer away. So a drive that came up spotless can be furred with fresh seedlings by the end of the summer without the bottle having failed at anything. Stopping those later ones is a residual job, a different chemistry with different rules attached.

Four answers come out of two questions:

Root yes, next flush no. A plain glyphosate product, ready-to-use for a few weeds and a concentrate for an area. This covers most gardens.
Root yes, next flush yes. A residual, meaning diflufenican with glyphosate. Check the surface wording before it goes anywhere.
Root no, next flush no. A contact acid, for a tidy-up before people come round. You are buying appearance, not a kill.
Root yes, and grass you want to keep. A selective, which is a lawn treatment and a different aisle. I do not cover lawn products here, and a hard-surface product will wreck a lawn.

Nearly every disappointed review of a weed killer is somebody who answered question one with a contact product or question two with glyphosate. The bottle did what it was built for. It was bought for the other quadrant.

The part of the decision that is about your ground, not your weed

If you answered yes to the second question you are shopping for diflufenican, and the amateur choice is narrower than the shelf suggests. There are exactly four amateur registrations for it in Great Britain, all of them Pathclear products under one company, and getting hold of one has become harder than it used to be.

Here is the bit that is not on the front of the box. Those products are approved for natural surfaces not intended to bear vegetation and for permeable surfaces overlying soil. Their own labels rule out impermeable surfaces and anything laid over impermeable material, which includes concrete, tarmac and paved areas, because the treated water runs off them into drains and onto ground it was never assessed for. A brick drive over a solid base is precisely the surface most buyers have in mind and precisely the one the label excludes. What that means in a real paving joint, and how long the residual genuinely holds, is worked through on the driveway and patio weed killer resource, and the plain yes-or-no version is on whether path and drive weedkiller works on block paving.

The brand name will not steer you here either. The same company sells the residual line and a set of contact bottles that leave nothing in the ground whatsoever, and what has been happening to that range recently is worth reading before you go hunting for a Pathclear. It is set out on the Weedol resource.

Four phrases on the front of a bottle that are worth nothing

None of these is a lie exactly. They are just words with no regulator behind them, and they are doing most of the persuading in this aisle.

"Professional strength" and "industrial". Great Britain classifies a plant protection product as amateur or professional and stops there, so industrial is not a grade anything can be. And the professional tier is not the locked cabinet people imagine: the amateur ceiling of 360 g/L glyphosate is the same concentration as Roundup ProActive, the standard professional amenity product. Professional bottles reach 550 g/L at the very top, which is a stretch rather than a chasm, and the line between the two registers is about training, not potency. Both using and buying a professional product require a specified certificate, or working under the direct supervision of somebody who holds one, so that tier costs you a legal obligation rather than a stronger spray. The full ladder, register by register, is on the strongest weed killer UK resource. Worth knowing before you order anything off a trade site: one well-known name, Rosate, has no amateur product at all and never has had one, so there is no version of it a homeowner may lawfully put through a sprayer.

"Pet safe" and "child friendly". There is no such approval to hold. It is a marketing phrase sitting on top of a label sentence that turns out to be near enough identical whichever active is in the bottle, and the hazard classifications at concentrate strength run the opposite way to the assumption. What to actually do with an animal in the house is on the pet safe weed killer resource.

"Extra tough", "max strength", "super concentrated". The pack in your hand has to carry the authorisation number and the concentration of every active in it. The listing you buy from does not, and hardly any of them bother. So the words on the front are chosen freely and the one number that settles the argument is the one you cannot see until it arrives. How to look it up in about thirty seconds, and what each retailer actually stocks, is on the where to buy weed killer resource.

A brand name on its own. Not one of the big names in this aisle sells a single chemistry, and inside a range a systemic bottle and a contact bottle can be one word apart on the label. That is why each name gets a decode on this site rather than a verdict, and the Resolva resource is the one to read if you want to see how far that can go under a single shelf brand.

What I would actually buy, for the three gardens people write to me about

A drive, a path or a patio, weeds in the joints. A 360 g/L amateur concentrate through a pump sprayer, mixed at the rate the label gives, on a dry morning with nothing forecast. Since there is no lawful step up from there for you, the shopping genuinely stops at that bottle rather than at the next bigger claim on the shelf. Gallup Home and Garden is one of the ordinary amateur bottles sitting on that number, and its rate and coverage are worked out under what the Gallup amateur label asks you to mix. Expect two to four weeks before it has finished, not two days.

A few weeds, once or twice a summer. A ready-to-use trigger bottle, and no guilt about it. It is the dearest way to buy glyphosate per gram and comfortably the cheapest way to deal with fifteen weeds, because a concentrate you use twice and then leave in the shed has saved you nothing.

A bramble, an ivy stem or a stump. Triclopyr, and on a stump the mix goes onto the cut face with a brush within minutes rather than through a sprayer. Glyphosate will do a bramble in time, but the woody-weed product is built for it and behaves differently, which is set out on the SBK and brushwood killer resource.

And whatever you buy, the thing that separates a result from a wasted afternoon is not the bottle. It is spraying onto dry leaves with a dry few hours ahead of you, wetting the foliage without drenching it, and then leaving it alone long enough to work. If it still looks green after a week that is normal, and how long weed killer takes to work explains what should be happening and when.

The one I would actually buy

This page routes you by job rather than crowning a single winner. But if you want the short answer for the commonest case, a systemic glyphosate concentrate at full amateur strength is it.

What I’d use

Glyphosate concentrate, 360 g/L

Gallup Home & Garden Glyphosate Weedkiller (1 litre)

The one Gallup a homeowner can legally buy and use: a 1 litre glyphosate concentrate at 360 g/L, approved for home and garden use under MAPP 17672.

It is the same active, the same 360 g/L loading and the same isopropylamine salt as the professional Gallup XL, and its single label rate of 24 ml per litre of water is exactly the rate the professional labels reserve for perennial broad-leaved weeds. What the two labels set apart is the authorisation printed on them rather than the strength, and this is the side of that line you are allowed to stand on.

Active ingredient: Glyphosate, 360 g/L, as the isopropylamine salt
Formulation: Soluble concentrate you dilute yourself
Approval: MAPP 17672, labelled for use only as a home and garden weedkiller
Mixing rate: 24 ml per 1 litre of water, per the label
Coverage: 40 sq m per litre of made-up spray, so roughly 1,667 sq m per bottle
Rainfast: Rain within 6 hours may reduce effectiveness, per the label
Size: 1 litre of concentrate

Watch out for

No measuring cap in the bottle. Check a cup arrives, or the dose is guesswork.
One re-treatment a season, and it takes four weeks. Do not go again early.
Not for lawns. It is non-selective and takes the grass too.
Resellers dominate the listing, so check the label that arrives is Barclay.
"Super strength" is keyword stacking. It is 360 g/L, same as professional Gallup XL.

Check the price on Amazon

That’s an affiliate link: buy through it and I earn a small commission at no extra cost to you. It doesn’t change what I recommend or what I say is wrong with it. More on how that works in the affiliate disclosure.

No brand pays for a mention here, and nothing on this page is a paid-for opinion. The card above is an affiliate link, so I earn a commission if you buy through it, at no extra cost to you. It buys no product a kinder write-up, which is why the watch-outs sit on the same card as the reasons to buy.

About this resource

I'm The Weed Guy, one bloke who is qualified to spray professional weedkiller. This page is deliberately a decision rather than a ranking, because I have not run these products against each other and I am not going to pretend I have. Every concentration and every count on it was read off HSE's public pesticide registers, which carry one list for amateur garden products and a separate one for professional products, and anyone can repeat the lookup.

Where a figure belongs to a specific product I have said which, and where a subject needs more room than a routing page can give it, I have sent you to the resource that does the work instead of summarising it badly here. There are no prices on this page at all, because a price read in one month is misleading by the next.

One date worth knowing before you stock up: glyphosate's Great Britain approval is under review rather than settled, so it is worth checking the current position rather than trusting any website including this one. Where that review has got to is tracked on whether glyphosate is banned in the UK.

Money, plainly. Nobody pays me to name a product or to leave one out, and this page in particular carries no recommendation, no buy button and no price. That is deliberate: a page whose entire job is to send you somewhere better should not end in a shopping basket, and the moment it does it stops being trustworthy about which direction to point you. The affiliate disclosure sets out how the rest of the site is funded.

Common questions

What is the best weed killer in the UK?

The job decides it, and there are only six jobs. If something has a root and you want it gone, a systemic glyphosate product, ready-to-use for a handful of weeds and a concentrate for anything bigger. If the ground has to stay bare afterwards, a residual instead, and read its surface wording before you buy. If it is woody, triclopyr. If it only has to look dead today, a contact acid, and accept it will be back. Any list that hands you a single winning bottle has quietly assumed which of those six you are, and it has probably assumed wrong.

Is Roundup the same as glyphosate?

No. Glyphosate is the active substance and Roundup is a brand that sells glyphosate products, along with several that contain no glyphosate whatsoever. That second half is where people come unstuck, because the fast-acting bottles under the same brand are usually pelargonic or acetic acid, which behave nothing like glyphosate. The name on the front settles nothing at all. The registered concentration does, and I have set the Roundup range out product by product on the Roundup resource.

What is the best weed killer for a driveway or patio?

It depends on whether you want it clear now or clear in October, and those are different bottles. Plain glyphosate kills what is growing in the joints today and leaves nothing behind, so the next seed that blows in germinates happily. A residual product adds diflufenican, which stops seedlings as they germinate, and that is the only thing that addresses the next flush rather than this one. The catch is the surface: the amateur residuals are approved for permeable ground over soil, not for impermeable surfaces like concrete or tarmac, which is a restriction almost nobody selling them mentions.

Do I need a licence to buy the strongest weed killer?

Not for the strongest one you can lawfully use, no. The amateur ceiling is a 360 g/L glyphosate concentrate and it sells over the counter with no paperwork, which happens to be the same concentration as Roundup ProActive, the standard professional amenity product. Professional products do go higher, to 550 g/L at the very top, but the professional register is not an open shop. Both using and buying a professional product are restricted: the regulations require a specified certificate, or working under the direct supervision of someone who holds one, and it is an offence to buy one for use by somebody who has neither. So the honest answer is that the strong stuff is already available to you, and the tier above it costs you a legal obligation rather than buying you a meaningfully stronger bottle.

Is concentrate better than a ready-to-use spray?

Better value, not stronger in the tank, and the difference matters. A trigger bottle holds single-digit grams of glyphosate per litre because it has already been diluted for you; a concentrate is sold undiluted at up to 360 and you add the water. Mixed to its own label rate the concentrate often ends up at a similar strength on the leaf, so what you are really buying is the right to stop paying for shipped water and the ability to do a whole drive from one tank. The price of that is a measuring jug and the discipline to use it.

What is the best glyphosate-free weed killer?

The best of them is still a contact herbicide, which is the thing to understand before you spend the money. Glyphosate-free bottles are almost always pelargonic acid or acetic acid, and both destroy the plant tissue they land on without ever entering the plant, so a seedling dies and anything with a root store regrows from it. They are genuinely quicker to look at and genuinely a poor buy for an established weed. There is also a wrinkle nobody expects: at concentrate strength these are the products carrying the hazard pictogram and the eye-irritation warning, while the glyphosate concentrates on the same shelf carry neither.

What is the best weed killer that kills everything permanently?

Two different products, and buying one while expecting the other is the commonest mistake on this whole subject. Killing everything is a non-selective systemic job, which glyphosate does properly, root and all. Keeping the ground empty afterwards is a residual job, which glyphosate cannot do at all because it leaves nothing in the soil. Nothing on the amateur register does both permanently, and the products that once kept a gravel drive bare for a season were withdrawn years ago rather than watered down.

Which weed killer is best for brambles and other woody weeds?

Triclopyr, and the reason is mechanism rather than muscle. It behaves like a plant growth hormone and sends a woody weed into fatal distorted growth, which is a completely different route in to the glyphosate one. Two things follow. It spares grass, so it suits a bramble in rough ground far better than a bramble in a planted border. And on a cut stump the treatment is a strong mix painted onto fresh wood within minutes of the cut, not a spray, which puts far more active into the stem than any foliar pass can.