Weeds in driveway cracks: how to remove them and keep them out
To get rid of weeds in driveway cracks, pull or scrape them out with a crack weeder after rain, kill what’s left with boiling water, a flame weeder or a spray labeled for driveways, then clean out the crack and seal it. The sealing step is what keeps them from coming back.
Contents
- Why do weeds grow in driveway cracks?
- How to remove weeds from driveway cracks by hand
- Natural ways to kill weeds in concrete cracks
- Which weed killer works best for driveway cracks?
- How to keep weeds out of driveway cracks for good
- What about weeds in a gravel driveway?
- Common mistakes with driveway weeds
- FAQ
Why do weeds grow in driveway cracks?
Concrete and asphalt don’t grow weeds; the soil that collects in cracks does. Dust, sand, leaves and grass clippings wash into every gap, weed seeds blow in after them, and the crack holds moisture and stays warm. Weeds such as prostrate knotweed, spurge, crabgrass and dandelions thrive there because nothing competes with them.
That gives you the plan for driveway weed control: remove the weeds, remove the soil they grow in, and take away the gap. It’s part of the wider approach in our guide to garden, driveway and gravel weeds.
How to remove weeds from driveway cracks by hand
- Wait for rain or water firstMoist soil lets roots slide out. University of Illinois Extension recommends pulling after the soil is moist from rain; Cornell suggests wetting the soil before weeding taprooted weeds.
- Use a crack weederA crack weeder has a narrow hooked blade that slides into the joint, cuts the root and lifts the weed and its soil out. An old knife or a flat screwdriver does the same in tight cracks — work carefully.
- Brush out the restA stiff wire brush or a paver brush clears moss, small seedlings and loose soil from joints.
- Flush the crackA hose or pressure washer blasts out remaining soil and seeds. It also blows out the sand between pavers, so plan to refill the joints afterward.
- Bag weeds with seedsDon’t leave flowering weeds on the driveway; seeds drop straight back into the cracks.
Natural ways to kill weeds in concrete cracks
Boiling water
Pouring boiling water slowly into the crack scalds the leaves, stems and shallow roots. It’s free, leaves nothing behind and is safe next to the lawn once it cools. Young annual weeds die; deep-rooted perennials often regrow and need repeat doses. Carry the kettle low, wear closed shoes and keep kids and pets away. More in our boiling water for weeds guide.
Vinegar
Household vinegar (about 5% acetic acid) burns the leaves of young weeds on a sunny day; a little dish soap helps it stick. It doesn’t kill roots, so perennials return. Horticultural vinegar (around 20–30% acetic acid) is much stronger and can burn skin and eyes: wear gloves and eye protection and follow the label. See our vinegar weed killer guide for mixing and limits.
Flame weeding
A propane flame weeder doesn’t need to burn weeds to ash: a quick pass that makes the leaves wilt is enough to rupture plant cells. Cornell’s weed science program notes flaming works on pavement, brick and pavers and best controls annual broadleaf weeds, while perennials need repeated passes. Never flame near dry grass, mulch, leaves, wooden fences or buildings, in windy weather, or when local burn restrictions apply, and keep water on hand.
Never use salt or bleach in driveway cracks. Salt stays in the soil and washes into the lawn and beds next to the driveway; bleach runs off into soil and drains. Never mix bleach with vinegar or other cleaners — the combination releases toxic chlorine gas.
Which weed killer works best for driveway cracks?
When natural methods can’t keep up, a store-bought product is the fastest option. Read the label: it must list driveways, walks or patios as a use site, and the weeds you have. In the US, the label is the law.
| Active ingredient | How it works | Best for | Limits |
|---|---|---|---|
| Pelargonic acid, ammonium nonanoate, acetic acid | Contact: burns the leaves within hours to a day | Young annual weeds, quick cleanup | Roots survive; repeat applications needed |
| Glyphosate | Systemic: moves to the roots, works over 1–2 weeks | Perennials that keep regrowing | No residual effect; kills any plant it touches, including lawn edges |
| Glufosinate | Mostly contact, faster than glyphosate | Mixed weeds and grasses | No residual effect; regrowth from roots possible |
| “Extended control” or “year-long” combination products | Kill existing weeds and leave a residue that stops new ones for months | Hard surfaces only, far from plants | Some move through soil and can injure tree and shrub roots; never in beds or gardens |
The last row needs care. University of Illinois Extension warns that some long-lasting products are soil-mobile and that misapplied ones can damage landscape beds and vegetable gardens and prevent planting there for months. Tree roots often run under driveways well beyond the canopy. If trees, shrubs or a lawn border the driveway, stick to contact products, glyphosate or non-chemical methods. Spray on a calm day, aim at the crack only, and keep pets and children off until the spray has dried or as long as the label says.
How to keep weeds out of driveway cracks for good
- Clean the crack fullyScrape, brush and blow out all soil and plant debris so the filler bonds.
- Seal concrete cracksUse a concrete crack filler or sealant sized to the gap. Fill narrow cracks directly; wider ones may need a backer rod first, as the product label explains.
- Fill asphalt cracksUse an asphalt crack filler, then consider sealcoating the driveway to close fine surface cracks.
- Refill paver joints with polymeric sandPolymeric sand hardens when misted with water, locking the joint so soil and seeds can’t settle in. Sweep it into dry joints, compact, brush the surface clean, then wet it exactly as the bag directs.
- Sweep or blow every few weeksKeep sand, clippings and leaves from building up new soil in the gaps.
What about weeds in a gravel driveway?
Gravel driveway weeds work differently: the whole surface is a seedbed once dust and leaves fill the gaps between stones. Raking, keeping enough gravel on top, and fabric under the stone are the main tools. Our guide to weeds in gravel covers gravel driveway weed control, pre-emergents labeled for gravel areas, and how to kill grass growing through gravel. If you’re clearing a large area of both weeds and grass, see weed and grass killer.
Common mistakes with driveway weeds
- Spraying and walking away. Dead weeds leave soil and seeds in the crack; new ones sprout within weeks.
- Pressure washing paver joints without refilling them. Empty joints fill with dirt and weeds faster.
- Using a residual “ground clear” product next to the lawn or under trees.
- Letting crack weeds flower. One plant of spurge or knotweed seeds the whole driveway.
Patios and sidewalks follow the same rules. For other hard-to-weed spots around the house, see natural weed killer options and the homemade weed killer recipes that are actually worth using.
FAQ
How do I permanently get rid of weeds in driveway cracks?
Kill or remove the weeds, clean the soil and debris out of the crack, then fill it: crack filler or sealant on concrete and asphalt, polymeric sand between pavers. Weeds need soil in the crack to grow, so a sealed crack stays clear. Sweep regularly so new soil doesn’t build up.
What is the best weed killer for driveway cracks?
For quick results on young weeds, a contact spray such as pelargonic acid, ammonium nonanoate or acetic acid. For perennials that keep coming back, a systemic nonselective product such as glyphosate reaches the roots. Use only products whose label lists driveways, walks or patios, and keep spray off lawn edges and beds.
Does boiling water kill weeds in cracks?
Yes, it scalds the top growth and shallow roots of young weeds and leaves no residue. Deep-rooted perennials like dandelions often regrow and need a second dose. Pour slowly from close range and wear closed shoes.
Should I use salt on driveway weeds?
No. Salt stays in the soil, washes into the lawn and beds next to the driveway, and can harm plants there for a long time. Concrete can also be damaged by salt. Boiling water or vinegar does the same job without the lasting harm.
What is a crack weeder?
A hand tool with a narrow hooked or L-shaped blade that slides into cracks and paver joints to cut and pull out weeds and the soil they grow in. Long-handled versions let you work standing up.
Related
- Weeds in gravelWeeds in gravel grow in the soil and debris between stones. Rake or pull them, spot-spray what’s left, then add fabric and enough gravel to keep them out.
- Boiling water on weedsBoiling water to kill weeds works in cracks and pavers on young annuals, with nothing left behind. How to pour it safely, and why perennials grow back.
- Vinegar weed killerVinegar weed killer burns young weeds within a day but rarely kills roots. Kitchen vs horticultural vinegar, recipe, results timeline, grass and safety.
- Garden beds, driveways & gravelGarden weeds in beds, vegetable plots, driveways and gravel: identify the common ones, pick the right method and tools for each place, and stop reseeding.
Updated October 3, 2026