Lawn edging can improve your yard aesthetically and keep grass from invading a flower border. Many kinds of grass spread via stolons (surface runners). Without lawn edging, you'll be pulling grass out of your flower beds all summer. Edging is one of the best ways to contain flower bed mulch and keep it from spilling into the yard. When installing lawn edging, take it a step further and install a mowing strip next to the edging.
A mowing strip is a narrow row of concrete pavers separating a planting bed from a lawn. But the difference between mowing strips and other kinds of edging is that the pavers in mowing strips are sunk into the ground so that the upper surfaces are flush with, or slightly above, the surrounding ground. When mowing the grass, you run two wheels on one side of your mower right on top of the mowing strip, eliminating the need for trimming. It's an efficient way to save hours of landscape maintenance.
Working With Concrete Edging Pavers
Precast concrete pavers with an interlocking-end connection system are an excellent choice for a mowing strip. The pavers shown in this project are 3 1/2 x 12-inch units from Edgestone. These have rounded ends so the pavers fit together for extra stability. The design also allows the pavers to form curves better than standard rectangular pavers. These pavers are also much heavier and taller than most paving bricks, so they're more likely to stay in place.
Mowing strips should be used in conjunction with another form of edging because they won't keep mulch from falling out of garden beds. Some people complement mowing strips with bricks placed on end, "shoulder to shoulder," to form edging. Less expensive metal or plastic edging also work well.
Equipment / Tools
- Tape measure
- Flat spade
- Carpenter's level
- Rubber mallet or small sledgehammer
- Precast concrete lawn edging pavers
- Lawn edging (optional)
Determine the Paver Height
Decide where you would like the top of the pavers to sit. This can be the same level as the grass or surrounding soil, or it can stand above the ground. Keep in mind that the pavers may sink gradually over time, so it’s a good idea to start with the pavers 1/2 inch above the ground so they won’t be recessed if they begin to sink.
Calculate the Trench Depth
Measure the height of the pavers to determine the depth of the trench you need to dig. The pavers will sit atop a 1- or 2-inch layer of sand in the trench. To calculate the trench depth, start with the paver height, subtract the height above ground that the pavers will sit, then add 1 to 2 inches for the sand layer. For example, if the paver is 3 1/2 inches tall and will sit 1/2 inch above the ground, the trench should be 3 1/2 – 1/2 + 2 = 5 inches (with a 2-inch sand layer) deep.
Establish the Paver Layout
Set the pavers end-to-end on the ground precisely to get a final layout. Make sure the pavers are butted snugly together.
Dig the Trench
Use a flat spade or a turf cutter to slice through the grass or soil on both sides of the paver line, keeping the shovel up against the pavers at all times. Remove the pavers and set them aside. Dig out the grass or soil between the two lines of sliced earth, using a mattock, trowel, or small shovel. Remove all grass roots and other vegetation. Flatten the bottom of the trench and step into the trench to compact the soil as you go. Check for consistent depth by setting a paver into the trench and comparing it to the ground level.
Add the Sand Layer
Fill the trench with a 1- to 2-inch layer of sand. Smooth the sand so it is flat and level. Check the resulting trench depth with a paver, as before.
Set the Pavers
Place the pavers into the trench, starting at one end of the trench and working toward the other. Fit the pavers tightly together so there are no gaps. After installing a few feet of pavers, set a carpenter’s level across the tops of the pavers to make sure their tops are flush with one another. They should be at the same distance above the ground (or flush, as desired), but they do not need to be level because the ground is not necessarily level.
Install Edging (optional)
Starting at one end of your planting bed, pound a segment of plastic or metal edging into the ground, using a rubber mallet or a small sledgehammer. Keep the edging right up against the sides of the pavers, on the garden bed side. Drive the edging into the soil to the desired height, based on how much material it is intended to contain.
Some types of edging interlock, as shown here; others such as galvanized metal edging should be overlapped by a few inches where the pieces meet. Secure the overlapped ends and all single ends with a long edging spike or staple, as applicable. Continue installing edging along the full length of the paver line, as desired.
Lawn Edging Tips
Mowing strips don't have to be flush with the grass for easy cutting, but they shouldn't be more than a couple of inches above the grass; 1/2 to 2 inches is ideal. When mowing a raised strip, tilt the mower back and set one of the front wheels onto the strip, then lift the matching rear wheel and set it on the strip. Keep the wheels centered on the strip as you mow so there's no danger of the mower's blade hitting the pavers.