Quick Take: The best way to keep grass out of your kitchen garden is to install a physical border — steel edging, brick, or stone — around the entire perimeter, then cover the interior pathways with gravel so grass runners have nowhere to go.

By Nicole Johnsey Burke: Founder of Gardenary and Author of Kitchen Garden Revival

Garden Setup Matters

I think we all know that boundaries are important, right?

When I set up my first kitchen garden, I made a classic mistake — I plopped my raised beds right on top of existing grass.

Without edging, here's what happened:

• The lawnmower tossed clippings straight into my vegetable beds
• The edger blade damaged my cedar boards
• Bermuda grass pushed up through the soil and stole resources from my vegetables

That's when I realized: to grow the plants I love, I had to stop the plants I don't.

A border was the answer.

Once I surrounded my kitchen garden with edging and spread gravel around the beds, everything changed — the space looked better, functioned better, and was so much easier to maintain.

The Importance of a Garden Border

The border is just as important to the garden setup as the raised bed, the soil, and the reliable watering system.

By separating the kitchen garden from the rest of the landscape, the border:

• makes lawn maintenance easier (you don't have to worry about a weed eater whacking your brand new raised beds)
• prevents the lawn and landscape from growing into the kitchen garden area
• designates the kitchen garden space as something special
• contains ground cover and landscape materials
• helps to keep the garden space tidy
• elevates the overall beauty of the garden

Plus, if you spread material like gravel underneath and around your raised beds, your garden space will dry much faster after rain. In that way, borders can not only help with drainage, they can actually increase the longevity of your raised garden beds. No more muddy walkways and wet blades of grass pressed up against wood.

By taking the time to plan for a border now, you’ll make life much easier for yourself and your garden later.

The Best Materials for Creating a Border in Your Garden

Free yourself to use a wide variety of border materials to separate the garden area from the rest of your yard and landscape. Possibilities include:

• simple blocks or bricks
• stone
• small boxwoods or other hedge-like plants
• high-quality steel edging
• hard plastic commercial landscape edging
• ornate edging (I only recommend this if you're separating inorganic materials that don't spread)

Bricks and stone can be beautiful, but I personally love using steel edging. It has a thin profile that can disappear behind the lawn, and it's relatively easy to install.

Here is what a boxwood border looks like. Notice this homeowner doesn't have to keep grass out of the garden space. (And if you look closely, you can see we still used metal edging to hold the gravel in place.)

If you're still deciding on the location of your garden, look for sunny areas next to a driveway, a fence line, or a patio that you could use as an existing border on one to two sides of your future garden space. In the backyard pictured below, we used the client's existing stone patio to border the kitchen garden on two sides. The brown edging between the landscape and the yard was already there, so we only had to add one side of border material.

What to Consider When Selecting Your Border Material

Keep strength, appearance, height, and durability in mind when picking out your border material.

Your Border Material Should Be Sturdy

I've found the most success keeping grass and weeds out of the garden when I elevate the entire space a couple of inches above the existing yard. This is only possible if the border material is thick and strong, not wiggling around and letting mulch or gravel escape. If you're purchasing steel edging, look for something with spikes to keep it in place.

Your Border Material Should Fit the Aesthetic of Your Home & Kitchen Garden

We use steel most often in our installations because it does a great job but is also very discreet in its design. It’s perfect for clients who want a more cohesive and natural look with their garden space. Make sure to select a steel color that matches accent colors on your home.

In the garden pictured below, we went with a stone border to match the existing stone around the client's landscaping.

Your Border Material Should Be Tall

If you have an aggressive grass like Bermuda that spreads via rhizomes underground, you'll want your border to be as tall as possible so that you can bury it several inches deep and still have a lip above the soil line to hold your ground cover in place. I recommend picking something at least 4 to 5 inches tall.

Your Border Material Should Be Durable

Go for the thickest piece of metal or plastic you can find so that you know your material will hold up over the years. Check the gauge of the steel you're considering. I always recommend buying the best of what you can afford at any given time to increase the longevity of your materials.

How to Calculate How Much Border Material You'll Need

Measure the length and width of your kitchen garden space. Here's the calculation you'll use to determine the total amount in feet you'll need of your material:

2(length of garden area in feet) + 2(width of garden area in feet) = total feet of material needed

Let's say your space is 30 feet long and 10 feet wide. Here's what the calculation would look like:

2(30 feet) + 2(10 feet) = 80 feet of material

Now, let's say that you only need to line three sides of your garden with border material because a concrete driveway will serve as the border along the back. Here's what your calculation would look like now:

1(30 feet) + 2(10 feet) = 50 feet of material

Once you have your total perimeter calculated, divide it by the length of the pieces you've selected for your border. If you're using steel edging, keep in mind that the edges overlap, which means a 10-foot border might only cover 9.5 additional feet once installed. Measure accordingly.

If you were going to use the steel edging available in the Gardenary shop, you'd divide your total footage by 15.5 feet (that's how many feet each package can cover).

50/15.5 = 3.23

That means you'd need to purchase 4 packages to have enough steel edging to go around your entire space.

Supplies Needed to Install Edging

• Your edging material of choice
• Wood or metal stakes and string to create a straight line along border
• Measuring tape to keep lines straight and equidistant from stationary objects
• Spray paint to create bright straight line on ground (optional)
• Something to dig a trench (e.g., an electric edger, a hoe)
• Gloves to protect your hands

Extra Supplies for Steel Edging

You'll need a hammer or rubber mallet to secure the edging in place. It's a good idea to also use a little wood block to protect your steel from the hammer or mallet. You might need a pencil to mark on the edging where you'll make your corners.

Depending on the steel edging, you might need a hacksaw to cut the pieces at the corners. Some steel edging products can simply be bent around a hard object.

Extra Supplies for Blocks or Bricks

You might need a masonry saw or a chisel and hammer to cut them.

Here are three steps to install edging material in your kitchen garden space.

Step One to Install Garden Edging

You know how you take the time to tape a room before you paint to ensure you have crisp and clean lines when you're done? That's what we want for our kitchen garden, too. A nice, straight line around your space will make it feel really special (and look professional).

Use stakes and string to make sure your lines are as straight as possible before you start digging.

Install stakes in the corners of your space using a hammer or mallet. Run string between the stakes, using a measuring tape to check that the string stays the same width from an existing structure like a fence or your home. Place your string at the bottom so you can see it clearly in step two. Another option would be to spray paint a bright line on your grass.

This step might feel annoying when you're raring to go and install your border, but it's essential. I've seen too many clients throw down some steel edging, only for them to step back and see an obnoxious curve in the very middle. A border is another part of the investment in your kitchen garden, so it's worth it to take the time now to do it right.

Step Two to Install Garden Edging

Digging a trench around the entire perimeter of the garden space is the best way to secure your border material, no matter what you've selected. Not only does this trench help hold your edging in place, it also makes it more difficult for weeds or vegetation to grow into the garden area. You may want to hire someone or enlist some help for this part.

If you're working with steel edging or plastic, the trench doesn't need to be very thick at all—just thick enough to slide your edging down.

Use a hoe or edging tool to dig a trench deep enough to hold your border material firmly.

• For a 6-inch piece of steel edging, I recommend digging a trench at least 4 inches deep.
• For a 4-inch-thick block, I recommend digging a trench at least 2 to 3 inches deep.

As you dig, check with your border material to be certain the height of the border is correct and continue to check your line for straightness. In the picture below, the border is measured against a permanent structure to ensure straightness.

If you're using stone as your border material, you might want to put a little bit of sand at the bottom of the trench to keep your stones in place.

Step Three to Install Garden Edging

It’s time to set your border materials into place. For steel edging, the most complicated aspect will be handling the corners. If it’s a thinner piece of edging, you can usually create a corner by bending the steel over a wooden block or another hard material. If it’s landscaper grade, you may need a steel cutter to bend the steel.

Once you've got your edging in place, position a wood block over each little section and hammer it in gently with a mallet.

If you're using steel edging that comes with little metal stakes, you'll use your mallet to hammer those in place, as well. Gardenary's steel edging slides together to easily connect. You can use a little screwdriver to push the steel through the connection if you're having trouble. Make sure that the brackets go on the inside of your space.

Now you're ready to add ground cover to your garden space!

Time to Add Garden Edging

We love borders at Gardenary, and we're willing to bet you'll soon see how important and beautiful they can be in your garden, as well. No matter if you’ll be doing your own maintenance or hiring a landscaper to help you, it will keep your garden area looking its best and hold all your landscape material in place.

Most importantly, it'll keep pesky grass runners out of your garden space!