Damaged lawn edges can make even a well-kept lawn look untidy. Whether the edge has crumbled, grass has crept into the border, or edging materials have shifted out of place, repairing the edge restores a crisp boundary. This guide walks through the steps to repair lawn edges and borders, drawing on advice from the Royal Horticultural Society and the University of Illinois Extension, along with essential safety reminders from the 811 service. For more on keeping borders neat, see our Border Repair category.
Re-establishing the lawn edge line
The Royal Horticultural Society (RHS) explains that a well-defined edge starts with a clean, continuous cut. To re-establish a straight edge, tie a string line between two canes or pegs at ground level. For curved edges, use a flexible garden hose, rope or string to mark the shape. The RHS suggests viewing the marked-out edge from different angles, including from an upstairs window, to check the shape before you begin cutting.
Once you are happy with the line, use a half-moon edging tool or a flat-backed spade. The RHS advice guide recommends inserting the blade fully into the ground, standing on the flattened top of the half-moon tool to drive it in. If you use a flat-backed spade, mark a depth of 7.5 cm (3 in) on the blade with tape and insert it to that depth. Work your way along the line, taking small steps so that each cut slightly overlaps the last, creating a continuous edge. Then go back along the line and pull up narrow strips of grass by hand. For larger pieces, slide a spade underneath to lift them away. The RHS notes that the removed turf can be composted or stacked separately to rot down into soil. A sharp manual edger makes this job much easier.
Restoring the drop to keep borders tidy
An edge that has lost its vertical drop allows grass to spread into beds and mulch to spill onto the lawn. The RHS recommends maintaining a drop of about 7.5 cm (3 in) from the lawn surface down to the border. This small cliff helps keep plants off the grass and grass out of the border. After re-cutting the edge, use a spade to remove excess soil or draw soil away from the lawn edge with a hoe. The RHS also suggests using a narrow rake to tidy up loose soil and cut grass. Regular trimming with edging shears after mowing will keep the drop crisp and prevent the edge from becoming overgrown again. For a full rundown on keeping edges neat, read our lawn edge maintenance guide.
Fixing heaved or loose edging materials
Metal and plastic edging strips can shift over time, especially in regions with freeze-thaw cycles. Rhonda Ferree, horticulture educator with University of Illinois Extension, notes that steel edging has problems with frost heaving in winter. Plastic edging, while inexpensive and easy to install, often has poor durability and can be frustrating to keep in place. Ferree says that of all common edging materials, plastic is probably the hardest to install for a lasting, stable edge.
To prevent frost heave, the Illinois Extension recommends using grooved or lip-style edging, along with steel anchoring stakes and proper installation procedures. Ferree adds that round-top plastic edgings are generally better than flat types because they do not sink as easily. If flat plastic edging is already in place, you can improve stability by nailing a 1 x 1 inch strip of treated wood along the bottom of each section, using galvanized nails. For metal edging, check that the stakes are driven firmly and that the edging has not been pushed upward. If the edge has heaved significantly, you may need to remove it, re-trench the bed, and reinstall it following the manufacturer’s instructions. Learn more about metal edging and plastic edging options.
Working without compacting the soil
Wet soil is easily compacted, which can harm grass roots and make future edge maintenance harder. The RHS advises avoiding work on frozen or very wet ground. If the soil is only slightly wet, you can reduce compaction by working off a wooden board. Place the board on the lawn next to the edge and stand or kneel on it while you cut and trim. This spreads your weight and protects the turf. The RHS also suggests that redefining lawn edges is often a good job for the quieter winter months, but if your soil sits wet over winter, it is best to wait until it dries out.
Before you dig: contact 811
Any project that involves digging deeper than a few inches can strike buried utility lines. The national 811 service reminds homeowners and professionals to contact 811 or visit their state 811 center’s website a few business days before digging. This includes common tasks such as installing edging, planting trees or shrubs, or resetting border materials. When you contact 811, you will need to provide the address, county, nearest cross street, and the exact area where you plan to dig. After you submit a request, wait a few days for utilities to mark the approximate location of buried lines with paint or flags. Then dig carefully around any marks and consider relocating projects that are close to buried utilities. The 811 service emphasizes that even shallow digging can damage lines, as some utilities are buried just inches below the surface.
Checklist for repairing lawn edges
Use this step-by-step list to work through a damaged edge repair:
- Mark the desired edge line with string (straight) or a hose (curved) and check the shape from several angles.
- Cut along the line with a half-moon edger or flat-backed spade, overlapping cuts to form a continuous edge.
- Remove the strips of grass and excess soil, and compost the turf or stack it to rot down.
- Restore a drop of about 7.5 cm (3 in) from the lawn to the border, using a spade or hoe.
- Inspect any metal or plastic edging for heaving. Reset loose sections, add stakes, and consider grooved or lip-style edging to resist frost movement.
- If the soil is damp, work off a wooden board to avoid compaction.
- Contact 811 a few business days before any digging that goes deeper than the existing edge.
- Trim the repaired edge regularly with edging shears to keep it crisp.
Frequently asked questions
Can I repair lawn edges in winter?
The RHS says you can redefine edges with a half-moon tool at any time of year, but avoid working on frozen or very wet ground. If the soil is only slightly wet, use a wooden board to reduce compaction. In mild winter spells, grass continues to grow, so occasional trimming may still be beneficial.
How deep should the edge cut be?
When cutting a new edge with a flat-backed spade, the RHS recommends marking a depth of 7.5 cm (3 in) on the blade. A half-moon edger is designed to be inserted fully, so stand on the flat top to drive it in. The finished drop from lawn to border should also be about 7.5 cm (3 in) to contain mulch and stop grass spread.
What if my plastic edging keeps popping out?
Rhonda Ferree of the University of Illinois Extension explains that round-top plastic edgings resist sinking better than flat types. If you have flat plastic edging, you can nail a 1 x 1 inch strip of treated wood along the bottom edge with galvanized nails to help stabilize it. For a longer-term fix, consider replacing it with grooved or lip-style edging secured with steel stakes, which the Illinois Extension says can stop most frost heaving.
For more detailed guides on lawn border repair, visit our Border Repair category page.
