The best weed killer is the easiest way to keep your lawn weed-free without harming the grass. If it's just a few weeds you're tackling here and there, you may as well pull them out by hand; but if you are noticing that you garden is increasingly overrun by weeds, then weed killer is probably the best solution.
Some weeds a re very resilient and even survive frosts; so, if you're finding lots of weeds despite the first frosts, consult our guide for the most effective products to deal with them quickly. All our top picks will do the job efficiently, and a couple are eco-friendly. Some also will nourish your lawn as they suppress weeds, so check these out if you want the best of both worlds.
Scroll on to see our top choices, then consider buying one of the best lawn mowers to also make a difference to how neat your lawn is.
The best weed killers
Yes, you read that right. Our first-choice weed killer might be a fertiliser, but as well as encouraging new growth in all the right places, it inhibits it where it counts. That is to say, in the process of slowly releasing nutrients over twelve weeks to sustain grass growth, its high potash content sees to it that stubborn moss is destroyed, and prevents the development of new patches. It also contains bacilus subtilus sp which is said to consume dead material like thatch, meaning less of your time spent scarifying.
Using a unique combo of three selective herbicides, Weedol lawn weed killer is formulated to target the most commonly occurring culprits when it comes to weedy lawns, killing dandelions, daisies and clover as well as lesser-known (but no less irritating) creeping buttercup, hogweed and others. It works by targeting weeds at the roots, and only requires one treatment per season to do its job, making it one of our most foolproof formulations.
This hardworking targeted weed spray from Neudorff is especially effective against stubborn, quick-spreading weeds such as goutweed and field horsetail. Delighted users report that this works wonders against these weeds where other weed killers fail to eradicate them. It also works in temperatures as low as 5°C, which means you can go ahead and eradicate weeds on your lawn without needing to wait until late spring. What we really like about this spray, though, is that despite being so fast-acting and effective against tough weeds, it's relatively gentle on the soil in your garden and has low toxicity to bees. High effectiveness, low environmental impact? Yes, please.
According to reviewers (and to Weedol), Rootkill Plus is powerful stuff – it promises visible results within just 24 hours, which users attest to, but it’s far from just a speedy slapdash solution. Withering the whole of the weed from the tip down to the roots so that it can’t come back, gardeners found this lawn weed killer worked wonders on stubborn bindweed and even brambles, and loved the convenience of the large container with its accompanying sprayer.
Like our previous pick from Weedol, the Resolva 24H ready to use weed killer claims to kill weeds in – yep, you guessed it – just 24 hours. In fact, when you take into account the matching 3 litre ready-to-use spray, super fast action and promise to annihilate weeds from root to tip, they’re more alike than different. Where this particular weedkiller comes in handy is with its combination of herbicides diquat and glyphosate, with the former being included to make the latter work more quickly and effectively, great if you’re in a rush to get the lawn in tip-top condition.
This brilliant product from Westland is a holistic all-in-one feed for your lawn; not only will it prevent weeds and moss, it will also condition your garden, making it look healthy and fresh. Most importantly, it is guaranteed to be safe to use around children and pets. Users report high efficacy, but some notice an unpleasant smell. However, the smell does fade over time.
How to buy the best weed killer
Quick links to buy weed killer
Whatever type you choose, there are a few general guidelines to follow. First, find out in advance if there’s likely to be inclement weather within 24 hours of application, and if so, take a rain check, as a downpour will lessen the effectiveness of the treatment. Then, be sure to take care following application to keep children and pets off the lawn for the time recommended by the manufacturer.
What is the best weed killer?
The best weed killer on our list is the Mo Bacter Lawn Fertiliser (opens in new tab): it conditions your lawn while tackling troublesome weeds.
Do I need a weed killer?
Of course, if your garden is overgrown and looking untidy, a weed killer may be necessary. However, in many cases, hand-puling may well be the best method for getting rid of weeds, and there are some plants that are often classed as weeds, but they're actually hugely beneficial to pollinators and can look quite nice as part of a natural-looking lawn. So, if they don't bother you too much, consider keeping them to help bees. There might be certain 'weeds' you don't want to eradicate.
1. Dandelion: highly beneficial to pollinators, and the leaves and flowers are edible.
2. Clover: very important to pollinators, it helps condition your lawn by improving nitrogen levels in the soil.
3. Chickweed: an important source of pollen in the spring, it’s also edible and tastes much like lettuce. Beneficial for lawns.
When is the best time of year to kill weeds?
Weeds will obviously be most active during the summer, but many will grow well into autumn, even after the frosts arrive. Mid- to late autumn is actually the best time of the year to tackle stubborn weeds, especially if you're gonna bring out the big chemical guns. The reason is that you can use the stronger stuff at this time of year without harming pollinators or young plants you want to keep. You should, of course, still be careful not to get weed killer on any perennials. For best results, choose a dry day for applying your weed killer to ensure maximum penetration.
DIY weed killer recipes
If you’re not sure whether you want to use a commercial weed killer, try these simple, eco-safe remedies:
- Pour boiling water on the weeds.
- Add table salt to a solution of dishwasher liquid, and pour over the weeds.
- Always mulch your borders, which will prevent weeds from spreading on to your lawn.