Weeds: The plants that refuse to die?
Sometimes the fight against weeds can seem futile. We might spend all afternoon on our knees ridding our driveways, paths, and patios of them; only for more weeds to reappear almost instantly. People can spend thousands with top driveway builders one year and then forget about the upkeep which can be a chore.
In this article, we’re going to look at ways to permanently kill off weeds from hard surfaces including:
- Concrete and stamped concrete
- Block paving
- Resin surfaces
What are Weeds?
A weed is any plant that grows where it’s not wanted: in the cracks between block paving, on gravel paths or drives, in gutters, etc.
There are many different types of weed, but things they all have in common include:
- Abundant reproduction
- Rapid establishment and spread
- The ability to spread in areas disturbed by human activity
- Seeds which can lay dormant for long periods of time
In other words, weeds do everything we don’t want them to do!
Why do weeds grow?
Weeds grow because they can, simple as that. Given the right condition for weeds to grow, nature will take its course no matter how much we’ve spent on our driveways or gardens.
Which weeds are most common on hard surfaces?
Some of the most commonly found weeds on hard surfaces include dandelions, plantain, meadow grass, couch grass, and the dreaded Japanese knotweed.
Unfortunately, most of these weeds are tough to kill and are perennial, meaning they can survive all year round.
What Weeds Are: Key Takeaways
- Weeds are any plants that grow where they’re not wanted
- Weeds will grow and spread wherever they can
- Most weeds on hard surfaces can survive in all conditions
How to Kill Weeds Permanently on Hard Surfaces
There are two approaches to tackling weeds. Killing weeds that are already there and preventing weeds from growing in the first place.
Although prevention is better than cure, you may be looking for a way to permanently kill existing weeds. With that in mind, we’re going to look at ways to both prevent and cure weeds.
How to Kill Weeds Permanently on Concrete Surfaces
Examples: Weeds on driveways and paths; stamped concrete surfaces
The bad news is that if your concrete surface has cracked or chipped and weeds have got through, you may not be able to kill them permanently to get rid of them.
Prevention: When laying a new concrete surface, lay two sheets of weed control or landscape fabric underneath. These will stop weeds from growing through the concrete.
Weeds thrive in damp conditions. Making sure your driveway is sloped enough to allow rain to drain away can help deprive weeds of the opportunity to root.
Cure: If weeds have grown through the concrete, then it’s a case of pulling them up as and when (being sure to get as much of the weed root as possible), and treating the area with a commercial weed killer. If you’ve got pets or are worried about environmental damage, boiling water or vinegar can also kill weeds.
You may also be able to reseal parts of the surface with a DIY concrete repair kit.
How to Kill Weeds Permanently on Paved Surfaces
Examples: Weeds on driveways, paths, gardens, and patios.
Prevention: At some point, it’s likely that weeds will appear in the cracks on a paved surface. These weeds aren’t growing up from beneath the surface. Instead, they’re growing from seeds that have blown into the sand used to fill the gaps between paving stones. As dirt also accumulates in the gaps, so weeds will flourish.
This means that, apart from making sure there is weed control fabric beneath your paving, the only prevention is to maintain your paving. You can do this by regularly brushing and washing it, using a sealant or launching a pre-emptive strike by using weed killer.
Cure: Once weeds have appeared in your paving, you can easily remove them manually. This can be done by hand or by using a special weeding tool for paving. You might also kill the weed first by pouring boiling water over them, spraying weed killer or using a flame gun.
To stop weeds coming back in a hurry, the next step is to clean the surface with a pressure washer. This will remove the gunk from between the slabs and also some of the sand. The gaps can then be refilled with fresh paving sand.
How to Kill Weeds Permanently on Gravel Surfaces
Examples: Weeds on driveways, paths, sections of gardens
Prevention: With gravel surfaces, even thorough prevention won’t guarantee freedom from weeds. Over time, the pressure of people walking and driving on it will cause pieces of gravel to pierce the weed control fabric, allowing weeds to grow through.
The most comprehensive weed prevention measure, in this case, is to replace the weed control fabric every couple of years.
Even then the surface is still susceptible to airborne seeds which can settle amongst the gravel and begin the weed growing process. The best prevention for this is to regularly rake your gravel. This will disturb any dirt and kill seeds, making it harder for weeds to establish themselves.
Cure: If weeds are growing from below then it’s very difficult to remove the root without further splitting the fabric. The best method is to use a specific weeding tool such as a corkscrew weeder.
Weeds can also be killed with weed killer, boiling water, vinegar or salt (note: salt is okay for hard surfaces but very bad for soil). Ultimately, however, a deteriorating fabric will have to be replaced.
If weeds have rooted above the fabric, they can be killed by any of the methods described above and removed by hand.
How to Kill Weeds Permanently on Resin Surfaces
Examples: Weeds on driveways, paths, patios, terraces
Prevention: Resin surfaces pride themselves on being weed resistant. Laid on top of concrete or asphalt, resin doesn’t allow weeds to grow through it. The only danger comes from weeds growing on the surface. This can be prevented by regular surface cleaning and brushing.
Cure: If weeds do establish themselves on resin surfaces, they can be removed manually.
A note of caution: If using weed killer on resin, be sure to use a mild or diluted substance as strong weed killer can dis-color the surface.
How to Kill Weeds Permanently on Walls
Examples: Weeds on garden walls, exterior walls
Prevention: Weeds that grow on walls come from airborne seeds nestling into accumulated dirt in the mortar and hard to kill. The best way to prevent this is to keep your walls clean or treated (taking care if there are plants you want growing up or near the wall).
Cure: Weeds that are growing between the bricks on your wall can easily be killed and manually removed with any of the methods described above. Just remember that flame guns or strong weed killer may stain or mark the bricks.
How to Kill Weeds Permanently: Key Takeaways
- Prevention is the best cure
- But prevention is not always permanent
- Weeds can grow from below or above on some surfaces
- Pick the right tools for the right surface
Happy weed killing!