How to Kill Weeds on Your Driveway

Driveway weeds are more than an eyesore – they’re a sign of damage that will only get worse if ignored. Every weed you see has roots working into cracks and gaps, gradually widening them and creating more space for future growth.

The good news is that driveways are one of the easier places to control weeds. Unlike gardens where you need to protect surrounding plants, you can treat driveway surfaces aggressively. The challenge is matching your approach to your surface type.

Driveways attract many of the same common UK weeds that appear elsewhere – dandelions, grass, and annual weeds that exploit any crack or gap.

Surface Types and Their Problems

Tarmac and Asphalt

Tarmac driveways develop cracks over time from frost damage, root pressure, and general wear. These cracks fill with windblown soil and debris, creating perfect conditions for weed seeds to germinate.

Once weeds establish in tarmac cracks, their roots accelerate the damage. Water gets into the cracks, freezes in winter, and expands them further. A small crack with a few grass shoots can become a major split within a couple of seasons if left untreated.

Block Paving

Block paving weeds grow in the joints between blocks where sand or pointing has degraded. Over time, the gaps fill with soil and organic matter – the perfect seed bed. For detailed guidance on block paving specifically, see our complete guide to killing weeds on block paving.

Gravel

Gravel driveways present a different challenge. If the underlying membrane has failed or never existed, weeds grow up through the stones from the soil beneath. Even with good membrane, soil accumulates on top over time and seeds germinate in the gravel layer itself. See our guide to killing weeds in gravel for specific advice.

Concrete

Solid concrete is relatively weed-resistant, but weeds colonise the edges where concrete meets soil, and any cracks or joints that develop. Expansion joints between concrete slabs are particularly vulnerable.

Killing Existing Weeds

For most driveway weeds, a systemic weed killer is the fastest and most effective solution. Glyphosate-based products are absorbed through the foliage and kill the entire plant including roots – important because you need to eliminate the roots to prevent regrowth.

Apply when weeds are actively growing, typically spring through autumn. The foliage needs to be healthy enough to absorb the herbicide and transport it to the roots. Avoid treating during drought when plants are stressed and absorption is poor.

For driveways, you can also use residual weed killers that create a barrier preventing new germination for several months. These are ideal for hard surfaces where you don’t want anything to grow. Apply after clearing existing weeds for maximum effect. For persistent perennial weeds pushing through cracks, you may need the strongest weedkiller available.

Manual Removal

For small infestations, hand weeding works. Use a weeding knife or old screwdriver to lever weeds out of cracks, trying to extract as much root as possible. This is more effective when soil is moist.

Manual removal alone rarely provides lasting control – seeds constantly blow in and germinate in any available gap. Combine it with crack repair or follow up with a residual weed killer.

What About Home Remedies?

Vinegar burns foliage but doesn’t kill roots – weeds regrow. Salt works slowly and requires large quantities. Boiling water kills what it touches but is impractical for larger areas.

These methods can handle occasional weeds but won’t control a serious infestation or provide lasting results. For driveways, where you’re not worried about affecting surrounding plants, proper weed killer is more effective and ultimately more economical.

Preventing Regrowth

Killing existing weeds is only half the job. To keep your driveway weed-free long term, you need to address why weeds are growing there in the first place.

Repair Cracks and Gaps

For tarmac, seal cracks with appropriate filler before weeds can re-establish. Clean out loose material and any remaining root fragments first. Tarmac crack filler is available from DIY stores and is straightforward to apply.

For block paving, refill joints with kiln-dried sand or polymeric jointing sand after clearing weeds and debris. Polymeric sand hardens when moistened and provides better long-term weed resistance.

For concrete, repair cracks and reseal expansion joints. Flexible sealant works better than rigid filler for joints that need to move.

Keep It Clean

Regular sweeping removes debris before it can accumulate and create growing conditions for weeds. Pay particular attention to edges where soil washes onto the surface, and to any cracks or joints.

A monthly brush takes minutes but prevents the buildup that leads to weed problems. It’s the simplest and cheapest form of prevention.

Use Residual Weed Killer

Residual or long-lasting weed killers create a chemical barrier that prevents seeds germinating for several months. Apply after clearing existing weeds and cleaning the surface. Reapply according to product instructions – typically once or twice per year.

These products are specifically designed for hard surfaces and paths. Don’t use them near lawns or planted areas where you want things to grow.

Common Questions About Driveway Weeds

What kills driveway weeds permanently?

No single treatment kills weeds permanently – seeds constantly blow in from elsewhere. However, killing existing weeds with systemic herbicide, repairing cracks and gaps, and applying residual weed killer creates conditions where new weeds rarely establish. Regular maintenance keeps the problem under control indefinitely.

Does salt kill weeds on driveways?

Salt can kill weeds slowly, but it requires large quantities and repeated applications. It’s less effective than proper weed killer and can damage some surfaces. For driveways, commercial herbicide is faster, more effective, and often more economical when you factor in the quantity of salt needed.

How do I stop weeds growing through tarmac?

Seal cracks promptly before weeds can establish. Once weeds get into tarmac cracks, their roots widen the damage and create more space for growth. Kill any existing weeds first, clean out the cracks thoroughly, then fill with appropriate tarmac sealant. Regular sweeping prevents debris accumulation.

Will pressure washing remove weeds?

Pressure washing removes surface growth but doesn’t kill roots embedded in cracks or joints. Weeds typically regrow within weeks. Use weed killer first to kill the roots, wait for weeds to die, then pressure wash to clean the surface. This combination is more effective than either method alone.

What’s the best weed killer for driveways?

For killing existing weeds, a glyphosate-based systemic weed killer works on virtually all weed types and kills roots as well as foliage. For ongoing prevention, a residual weed killer creates a barrier against new germination. Many products combine both functions – check the label for “long-lasting” or “prevents regrowth” claims.

Driveway weeds exploit every crack and gap they can find. Pulling removes the top growth but roots stay anchored in the damage. A systemic weedkiller travels down to kill the entire plant – then seal those cracks before new seeds blow in.