how to stop weeds growing under decking

How to stop weeds growing under decking

Not many people think about weeds when they install their decking only to discover a few months later that green shoots start to pop up.

You can just use a salt or weed killer mix and that area will not see any weeds for many years. But this method will do more harm than good once it starts to spread around the garden and onto the lawn and the flower beds.

I then cover the weed barrier with sharp sand so there is no room for weeds to grow and take hold underneath the weed barrier.

You can remove a section of the boards and gently spread it underneath.

Fitting Your Weed Barrier

If your decking has already been installed then you can still use a weed barrier.

Cutting sections and overlapping by 2 feet is just as effective once you have pinned and covered with sand to hold in place.

Once you have pulled the weed barrier to the back of your decking you should use some tent pegs to hold it in place. Continue doing this until you have covered the area under the decking. Remember to overlap the weed barrier by 2 feet.

Installing A Weed Barrier

Because the boards have been installed in can be hard to spread out the weed barrier underneath the decking boards.

Like all weed solutions, there is the chemical version that will slowly destroy the soil around your decking project or the safer methods.

How to stop weeds growing under decking

Gravel is an attractive and useful ground covering. While, on its own, gravel may not stop all weeds from sprouting, combining it with landscape fabric creates a complete barrier. Apply 3–4 inches of gravel over your landscape fabric to keep the area underneath your deck weed-free.

Pre-emergent weed killers destroy weeds just as the seeds germinate. They won’t kill mature weeds, so apply pre-emergents early to make sure no weeds take root under your deck.

Add Gravel Over Landscape Fabric

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Use a Long-Term Weed Killer

Landscape fabric provides a water-permeable barrier over the soil that prevents weeds from sprouting. By laying landscape fabric, you prevent seeds and sunlight from reaching the topsoil, so even the toughest weeds have a hard time growing.