How to Keep Grass from Growing Under Fence

Having your lawn maintained and looking neat is every homeowner’s dream, but what’s daunting is discovering that you have grass growing under your fence. 

It’s more frustrating when your lawnmower can’t reach this grass. 

Keeping grass from growing under the fence may require you to use a weed eater or treat the vegetation with a herbicide.

There are other methods, but the two effectively prevent the growth of grass along the fence line.

Read on to learn why you need to prevent grass from growing under a fence and tips on how to keep it from growing under the fence.

Why Should You Prevent Grass From Growing Under a Fence?

A fenced property not only defines your property line and secures your space, but it also keeps your pets in. It also keeps your children safe and prevents them from wandering off when outdoors. 

Any grass growing under a fence may jeopardize your efforts to keep your kids and pets safe.

It also makes your yard look unkempt. 

Tips on How to Keep Grass From Growing Under a Fence

It’s common to have grass growing under a  fence. Below are some ways you can prevent grass from growing on this section of your property. 

  • Use a Weed Eater

A weed eater or weed whacker can help eliminate grass, weeds, or any other plant around your fence. You should note that a weed eater doesn’t kill the plant immediately, and you’ll need to use it regularly to prevent the grass from growing back.

It’s essential to ensure that the person using a weed eater is trained to operate it and wears protective clothing and gear. 

You also need to be alert as you don’t want the flying debris harming the people around you. 

The weed eater has a monofilament line that spins while chopping down anything around it.  It’s recommended to run the weed eater close to the fence without touching the wall.

That will remove any grass around it and still protect your fence from damage. 

Note that using a weed eater can destroy any plants around the fence.

That’s why you need to be cautious when using it around your fence or find an alternative method of removing the grass under the fence. 

  • Get a String Trimmer

Although not a popular method, using a string trimmer is an effective way to prevent grass from growing. 

To get started, mark a line that’s about six inches into the yard from the fence line using string and stakes. 

Ensure that you get an even line by measuring the distance between the string and fence in different places.

Do the same on the outside of the fence if it isn’t on the property line. The string marks the area you’ll mulch. 

Use a sharp garden spade to dig down two inches deep along the string. Remove the grass using the spade, but be cautious as you don’t want to destroy your fence’s bottom side.

For any remaining grass that you can’t remove with a spade, spray a herbicide, but do it on a day with no wind. 

Get some landscape fabric and trim it to the width of the exposed soil.  Place it under and around the fence line. Position some landscape staples on the edges to hold the fabric in place.

Cover the fabric with small rocks or mulch, and put the cover material into a level layer that is balanced with the surrounding grass. Mulch like bark chips and wood chips smoothers any weeds or grass and prevents their growth.

Avoid digging around the fence if it’s at the bottom of a slope as rain can fill the trench and rot the fence wood. 

The method works for grasses that grow in clumps.

Create a Long-Term Barrier

Another effective way to stop grass from growing close to the fence is to create a hardscape barrier.

You’ll find that some grass species find it difficult to pass through pavers, bricks, and other hardscaping barriers.

To create this barrier, you’ll need to dig a trench that is one and a half inches deeper than pavers or bricks.  The track needs to be an inch wider, close to the fence.

Place landscape fabric in the canal and fill it with sand. Lay the pavers or bricks on the sand and use a mallet to hammer them into place.

Make sure they are leveled using a builder’s level.  

Check to see if the pavers or bricks are a half-inch higher than the surrounding area. If you notice any gaps, fill them with sand.

  • Treat the Grass Using a Herbicide

You can also prevent grass from growing under the fence by spraying a herbicide on the fence’s base.  It’s one way to kill any grass, weeds, or plants without destroying your fence. 

The best thing about herbicide treatments is that you may only need one or two treatments annually to keep your fence line clear of any grass or weed.

Herbicides kill the entire plant, and that includes the roots. 

You need to be cautious when using any herbicide, as spraying it on a healthy lawn can lead to patches of dead grass. 

A homemade herbicide using vinegar and water can replace store-bought herbicides.

Commercial herbicide like Roundup is effective in killing unwanted plants. 

Have protective clothes on when using a herbicide to control invasive grass. Find a dry day to spray the product on the grass and weeds that are growing. 

Remove the growth after it’s died off. That may take up to a week or more. 

Use a pre-emergent weed killer to activate the grass barrier. You can also choose to use both products simultaneously, but you need to follow the instructions. 

Spraying a herbicide not only eliminates the invasive grass but also keeps your property looking neat and makes mowing simpler.

The method is inexpensive and guarantees long-term results compared to other methods. 


Maintaining a fence line doesn’t have to be daunting. If you’re dealing with grass that keeps growing under the fence line, you can control it using a weed eater, creating a barrier, or spraying herbicides. Some methods may take more work, but they will help keep your fence correctly maintained and neat. 

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