How to Kill Weeds in Artificial Grass

You bought artificial grass to escape the endless weeding. So why are there weeds growing in it?

Don’t panic. Weeds in artificial grass are common, easy to deal with, and almost always preventable once you understand why they appear. The good news is that killing them is much simpler than dealing with weeds in a real lawn because you don’t have to worry about harming the grass.

Why Weeds Grow in Artificial Grass

First, let’s clear up a misconception: weeds don’t actually grow through artificial grass. The backing material is impermeable to roots. What you’re seeing are weeds growing in one of three places:

Around the edges. The perimeter where your artificial lawn meets patios, fencing, or borders is the most common spot. Small gaps allow soil contact, and that’s all a weed seed needs.

Through drainage holes. Artificial grass has small perforations to let water drain away. If there’s no weed membrane underneath, weeds can push up through these holes.

On top of accumulated debris. This is the sneaky one. Leaves, dirt, and organic matter build up on the surface over time. Airborne seeds land on this debris and germinate right there on top of your lawn. These surface weeds have shallow roots and are the easiest to remove.

If weeds keep appearing despite your efforts, the installation may be at fault. Specifically, a missing or damaged weed membrane underneath. Worth checking if the problem persists.

Identifying Your Weeds

Different weeds require different approaches. Knowing what you’re dealing with helps you choose the most effective treatment. The same common UK weeds that invade real lawns will appear in artificial turf too, including dandelions, clover, and annual weeds that exploit any gap.

Surface weeds growing on debris tend to be annuals with shallow roots. These pull out easily and rarely return once you clear the debris layer. Edge weeds and drainage-hole weeds are more likely to be deep-rooted perennials such as couch grass or bindweed, which need chemical treatment to kill properly.

How to Kill Weeds in Artificial Grass

You have several options, from completely chemical-free to commercial weed killers. All work well on artificial turf because you don’t need to worry about harming the grass itself.

Pull Them Out by Hand

The simplest solution is often the best. Most weeds in artificial grass have shallow root systems (especially the surface weeds growing on debris). Grab them at the base and pull firmly. If they’ve rooted through drainage holes, you may need a bit more force, but they’ll come out.

This is genuinely the fastest method for small numbers of weeds. No waiting for chemicals to work, no equipment needed.

Hot Water

Pour hot water directly onto weeds and they’ll wilt and die within hours. This works by essentially cooking the plant cells. Wait until the weeds have wilted, then pull them out and discard. For more on this approach, see our full guide: does boiling water kill weeds?

Important: Use hot water, not boiling. Artificial grass is made from plastic, and boiling water can potentially damage or distort the fibres. Water from a recently boiled kettle that’s cooled for a few minutes is ideal.

Vinegar Solution

White vinegar is an effective contact herbicide. The acetic acid burns plant tissue on contact. Mix three parts vinegar to one part water in a spray bottle and apply directly to weeds. They should die within a day or two.

Downsides: vinegar only kills what it touches (the leaves), so deep-rooted perennials may regrow. It also smells strongly until it dries. For more on this method, see our guide to using vinegar as a weed killer. Horticultural vinegar (20% acetic acid) is stronger than household vinegar but still won’t kill deep roots.

Salt

Salt dehydrates plants and can be effective on small weeds. Sprinkle it directly on the weed or dissolve in water and spray. Combining salt with vinegar (50/50 mix) creates a more potent solution.

Be careful not to let salt run off into nearby flower beds or borders. It will kill anything it contacts and can damage soil long-term.

Commercial Weed Killer

For stubborn or widespread weeds, a proper weed killer is the most effective option. Glyphosate-based products work systemically. The chemical is absorbed through the leaves and kills the entire plant including roots.

Spray directly onto the weeds when they’re actively growing. Don’t spray the soil hoping to prevent future growth. Glyphosate only works through foliage. Be careful around any plants you want to keep, as it kills everything it touches.

For a full breakdown of the best weed killers available in the UK, including product recommendations, see our buyer guide.

Will Vinegar Damage Artificial Turf?

No. Standard white vinegar (5% acetic acid) will not damage, stain, or discolour artificial grass fibres. You can spray it directly onto weeds growing in or around your artificial lawn without any risk to the turf itself.

The same applies to horticultural vinegar (20% acetic acid), although you should wear gloves and eye protection when handling the stronger concentration. Neither version will harm the plastic or rubber components of artificial turf.

The limitation of vinegar is not safety but effectiveness. It only burns the leaves and stems it touches. Deep-rooted perennials like bindweed or couch grass will regrow from their roots within a few weeks. For those weeds, a systemic weed killer is the better choice.

Can You Use Roundup on Artificial Grass?

Yes. Roundup and other glyphosate-based weed killers are completely safe for use on artificial grass. Glyphosate only affects living plant tissue, so it has no effect on synthetic fibres, plastic backing, or rubber infill.

Spray it directly onto the weed foliage, and it will be absorbed through the leaves before travelling to the roots. The weed dies completely within 7 to 14 days. This is the most effective option for perennial weeds that keep regrowing after hand-pulling or vinegar treatment.

A few tips for using Roundup on artificial turf:

• Spray on a dry, calm day so the product stays on the leaves
• Don’t apply before rain. It needs at least 6 hours to be absorbed
• Avoid spraying near any real plants you want to keep
• One application is usually enough for annual weeds. Perennials may need a second treatment after 3 to 4 weeks

What NOT to Use on Artificial Grass

Some products that work fine on natural lawns will damage artificial turf:

Iron sulphate: Commonly found in lawn weed killers and moss treatments. It causes bright orange staining on artificial grass that’s extremely difficult to remove.

Bleach: While it does kill weeds, bleach can permanently discolour synthetic fibres. The staining may be patchy and very visible.

Boiling water: As mentioned above, the extreme heat can melt or distort plastic fibres. Stick to hot (not boiling) water.

Always check the label of any product before using it on or near artificial grass.

How to Prevent Weeds Coming Back

Killing existing weeds is only half the battle. Prevention is where you’ll save yourself ongoing effort.

Brush Regularly

Use a stiff brush with plastic bristles (not metal, which can damage the turf) to sweep your artificial lawn at least twice a month. Brush in the direction of the pile. This removes debris, seeds, and any organic matter that weeds could root into.

Regular brushing also keeps the grass blades upright and looking fresh, so you get a better-looking lawn while preventing weeds.

Remove Leaves and Debris

Don’t let leaves sit on your artificial lawn for weeks. They trap moisture, break down into compost, and create the perfect seed bed for airborne weeds. Clear them regularly, especially in autumn. A leaf blower makes quick work of this.

Trim Overhanging Trees and Hedges

The fewer seeds and leaves that land on your lawn, the fewer weeds you’ll get. Keep vegetation trimmed back from the edges.

Seal the Edges

Gaps between your artificial grass and hard surfaces (patios, paths, fencing) are prime weed territory. Seal these with a suitable filler or edging strip. This is where most weeds appear, and sealing prevents soil contact that allows them to root.

Check Your Weed Membrane

If weeds keep growing up through the drainage holes (rather than around edges or on the surface), the weed membrane underneath may be damaged or missing. This is usually an installation issue. A geotextile membrane should have been laid before the artificial grass went down. It blocks weeds while still allowing water to drain.

Apply a Pre-Emergent in Spring

If you’re dealing with recurring weeds every year, a pre-emergent herbicide applied in early spring can stop weed seeds from germinating. These products form a chemical barrier in the soil or substrate layer. They won’t harm the artificial turf and are especially useful around the edges where most weeds enter.

Seasonal Weed Management for Artificial Grass

Weed pressure changes throughout the year. Planning your maintenance by season keeps your artificial lawn clean with minimal effort.

Spring (March to May): This is when most weed seeds germinate. Apply a pre-emergent if needed, seal any edge gaps that have opened over winter, and start your regular brushing routine. Treat any perennial weeds that survived winter with glyphosate while they’re actively growing.

Summer (June to August): Peak growing season means weeds can appear quickly. Hand-pull surface weeds as soon as you spot them. Brush at least twice monthly to clear debris and prevent seeds from establishing.

Autumn (September to November): Falling leaves are the biggest challenge. Clear them weekly to prevent a debris layer forming. This is the most important season for prevention because rotting leaves create the perfect growing medium for spring weeds.

Winter (December to February): Weed growth slows dramatically. Use this quieter period to inspect the edges for gaps, check the membrane condition, and carry out any repairs. A quick brush after storms clears wind-blown debris.

Moss and Algae on Artificial Grass

In shaded, damp areas, you may notice green moss or algae growing on the surface of your artificial lawn. This is different from weeds but just as unsightly.

Do not use iron sulphate or ferrous-based moss killers on artificial grass. These leave permanent orange stains. Instead, use a diluted bleach-free moss treatment specifically designed for synthetic surfaces, or scrub the affected area with a stiff brush and a solution of warm water and washing-up liquid.

Improving drainage and reducing shade are the best long-term solutions for moss on artificial turf. Trim back overhanging branches to allow sunlight through, and ensure water drains away properly after rain.

Frequently Asked Questions

Why are weeds growing in my artificial grass?

Weeds appear for three main reasons: airborne seeds landing on accumulated debris on the surface, gaps around the edges allowing soil contact, or a missing or damaged weed membrane underneath. Surface weeds (from debris) are most common and easiest to deal with.

Can weeds actually grow through artificial grass?

No. Weeds cannot grow through the backing material of artificial grass itself. They grow around the edges, through drainage holes (if there’s no weed membrane), or on top of debris that’s accumulated on the surface. If weeds seem to be coming through the middle of your lawn, they’re likely growing through drainage holes due to inadequate installation.

What weed killer is safe for artificial grass?

Glyphosate-based weed killers (such as Roundup) are safe to use on and around artificial grass. Vinegar and salt solutions are also safe. Avoid anything containing iron sulphate (causes orange staining) or bleach (causes discolouration). Always check the label before applying any product.

Will boiling water damage artificial grass?

Potentially, yes. Artificial grass is made from plastic, and boiling water can melt or distort the fibres. Use hot water instead. Water from a recently boiled kettle that’s been allowed to cool for a few minutes is still hot enough to kill weeds without risking damage to the turf.

How do I stop weeds coming back?

Regular maintenance is key: brush the lawn twice monthly with a stiff plastic brush to remove debris and seeds, clear fallen leaves promptly, seal any gaps around the edges, and trim overhanging vegetation. If weeds persist, check that a proper weed membrane was installed underneath the turf.

Will vinegar damage artificial turf?

No. Both standard white vinegar (5% acetic acid) and horticultural vinegar (20% acetic acid) are safe for artificial grass. They won’t stain, discolour, or damage the fibres. The limitation is effectiveness, not safety. Vinegar only kills the visible parts of weeds, so perennials with deep roots will regrow.

Can I use a pressure washer on artificial grass to remove weeds?

You can use a pressure washer on a low setting to remove surface debris and shallow-rooted weeds. Avoid high-pressure settings as these can damage the turf fibres and displace the infill material. A standard garden hose or stiff brush is usually sufficient for routine cleaning.

How often should I brush artificial grass to prevent weeds?

Brush at least twice a month with a stiff plastic-bristled brush. In autumn when leaves are falling, increase this to weekly. Regular brushing removes organic debris before weed seeds can take hold, and it keeps the grass blades upright for a better appearance.

The Bottom Line

Weeds in artificial grass are annoying but easily dealt with. For most people, hand-pulling combined with regular brushing is all you’ll ever need. For stubborn cases, hot water, vinegar, or a glyphosate-based weed killer will finish them off.

The real win is prevention. Keep your artificial lawn clean, seal the edges, and you’ll rarely see a weed at all. Much easier than maintaining a real lawn, which was probably the point of going artificial in the first place.

For more advice on tackling garden weeds, visit our weed control guide or browse our weed killer products.