how-to-stop-weeds-growing-in-block-paving

How to Stop Weeds Growing in Block Paving

What’s the ultimate eyesore? Weeds in your block paving. They’re visible from a mile off and seem impossible to remove. 

But have no fear. This article will coach you through how to stop weeds growing between paving slabs, including removal methods and regrowth prevention.

Weed Removal

You’ll be pleased to know there are countless weed removal methods. There are three broad categories:

  • Mechanical control
  • Chemical control
  • Non-chemical control

*These techniques can be dangerous if you’re not wearing the correct safety gear. There’s a list of the essential protective equipment at the end of each section.*

Mechanical Control Methods

Manual Removal

This method involves picking each weed by hand. Avoid getting ahold of the leaves and aimlessly yanking. This will often break the stem, leaving the roots still intact under the soil surface. 

Instead, grip the plant and wriggle it free. Then, attempt to remove the whole plant, including the root network. 

Weeds are more easily removed from damp soil, so the optimal time for manual removal is after rain or once you’ve gone over the block paving with a hose. 

Safety gear: knee pads or a kneeler. 

Pressure Wash

Pressure washing is a great way to remove block paving weeds as the water’s force lifts the whole weed, including the root network, and displaces any weed seeds.

When you’re pressure washing, aim for the gap between the paving stones, not under the slabs themselves. This prevents disturbing the ground that the block paving lays on – you don’t want to end up with an uneven patio!

This method is a great short-term solution, but continually pressure washing your block paving can damage it. Instead, combine it with another method!

Safety gear: protective footwear. 

Chemical Control Methods

Chemical control is another great way to stop weeds growing in block paving. Removing them can be tricky, but with a weed killer, it’s a doddle.

There are lots of weed killers to choose from. Whatever one you use, read the instructions! These contain vital information on protecting yourself and getting the most use out of your weed killer. 

When choosing a weed killer, there are two main options:

  1. Selective
  2. Non-selective

Selective weed killers target just weeds; they won’t harm your surrounding plants. If that’s a worry for you, go for that one. If you’re not so worried, a non-selective weed killer will be fine.

But the decisions don’t end there. You also have to choose whether you want a contact, residual, or systemic weed killer. 

Contact weed killer

This option is ideal if you want a fast-acting weed killer and if the thought of damaging neighbouring plants is too difficult to bear! 

However, for this type of weed killer to work, the weeds must be in the active growth stage. Also, it only kills the leaves – the roots remain!

Safety gear: gloves and any other equipment listed on the weed killer’s instructions.

Residual weed killer

This is one powerful weed killing option; it poisons the soil, which is great for killing weeds but not so great if spread to other areas. 

If spraying, make sure you’re not treading the weed killer around in areas where you want your plants to stay alive!

Safety gear: gloves and any other equipment listed on the weed killer’s instructions.

Systemic weed killer

This is the weed killer that most people know about. It kills the weeds entirely, but it takes a long time to work. 

If you’re happy to wait 7 – 10 days, though, this is the best option to protect your neighbouring plants but still completely rid your block paving of wicked weeds.

When using systemic weed killer, check the forecast! If it’s washed off within 6 hours, it won’t work!

Safety gear: gloves and any other equipment listed on the weed killer’s instructions.

Non-Chemical Control

If chemicals aren’t really your thing, try a more organic weed killing approach.

Boiling Water 

boiling-water-kills-weeds

This method is as simple as boiling your kettle and pouring the water straight onto your block paving weeds. 

Boiling water kills weeds and stops them from germinating. Pour the boiling water from a low height to avoid it splashing up, and aim straight at the weeds. 

Safety gear: protective footwear.

White Vinegar

White vinegar dries weeds out.

You’ll need a higher concentration of white vinegar for mature weeds, but if your weeds are only young, a low concentration will work just fine.

Mix together:

  • 2 tsp dish soap
  • 4 ½ litres white vinegar
  • Water (if it’s a high concentration vinegar)

Dish soap allows the vinegar to bind to the weed’s surface. Apply the solution when it’s sunny because if it’s washed away by the rain, you’ll need to apply it again!

Repeat every month, six weeks tops!

Baking Soda

Dust the baking soda on your block paving, getting it into the gaps using a broom. Then, water it with a watering can or hose.

Again, repeat every month, six weeks at a maximum!

Salt Water

Make up a saltwater solution that’s 1 part salt, 3 parts water. Pour this in the gaps in your block paving. Once the weeds begin to die, sprinkle them with dry salt. If you’ve got a patch of well-established weeds, make sure to really cover these in salt.

You know the drill, repeat every four to six weeks!

Weed Prevention

So, you’ve removed the weeds from your block paving. Now, prepare your slabs and apply a block paving sealer to stop weeds sprouting back up. 

Sealing your paving slabs doesn’t just prevent weeds; it also protects and stabilises your block paving. It’s a great, all-round form of paving maintenance!

But before we get to the two simple steps, there’s a couple of things to consider.

Watch The Weather!

Keep an eye on the weather forecast, only applying sealer during a period of dry weather. This is essential because paving slabs soak up moisture from the rain, making them unable to absorb the sealant properly. 

Picking Your Sealant

Is your paving concrete or clay? Trust me, this matters! 

When choosing a sealant, pick one that’s specific to your paving material. Don’t fall for an “all-purpose” paving sealer – it’s a trick! 

When it comes to sealants, the cheap ones will let you down. The more you pay, the better the protection!

Step One: Prepare Your Block Paving

As you’re sealing up the gaps, you’re going to need to remove the existing weeds. Use one of the methods described earlier to do this. 

Then, clean and dry your paving. Allow it to dry thoroughly before applying the sealant. 

Step Two: Apply Block Paving Sealant 

Just like with weed killers, the first step when applying block paving sealant is to read the instructions. This gives you essential information on how much sealer to use and exactly how they recommend applying it. 

Apply the first coat of sealer. You can use a sprayer or a roller and tray – whatever your preference is! 

You want to saturate but not flood your paving slabs. Big puddles of sealant will take an incredibly long time to dry! Spray/roll in straight lines and take special care to apply the sealant to the joints. 

Then, let it dry. It’ll take around 3 hours. Once it’s fully dry, you can do the second coat. The thicker the sealant, the glossier appearance it’ll have!

Again, allow the sealer to dry. This may take up to 4 hours – don’t walk on it during this time, and wait a good 24 hours before parking your car on it. 

Final Point

Weeds are clever, but you’re cleverer! Using any of the methods in this article, whether mechanical, chemical, or non-chemical control or prevention using a block paving sealer, you can guarantee weed-free block paving! 

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