How to Install Metal Edging for Landscaping | Straight Lines That Last

For the full breakdown, see our best Edging For Landscaping guide.

A crisp border between lawn and flower bed is one of those details that separates a cared-for yard from a so-so one. Metal edging holds that line beautifully, but only if it goes in right. The job is straightforward — layout, trench, set, stake, backfill — but each step has a gotcha that can turn a weekend project into a re-do. Here’s how to get it clean the first time.

Mark and Clear the Path First

Don’t start digging until the line is drawn. Lay a garden hose or run stakes with builder’s string to trace curves and straight runs. Spray paint works on grass; chalk works on hard surfaces. Once the line is right, strip the sod or soil along the path — about 2–3 inches wide — and remove any rocks, roots, or debris. Tip: if the ground is hard or dry, dampen it with a hose an hour before you dig. Moist soil cuts far easier and won’t crumble the trench walls.

The Trench Depth Matters More Than You Think

Dig a trench roughly 1/2 inch to 1 inch shallower than the edging’s height. For standard corrugated metal edging, that usually means 2–4 inches deep — check your product’s specs. Too shallow and the edging wobbles; too deep and the top edge disappears or collects soil that grows grass over the border. The bottom of the trench should be flat and level so the edging sits straight. A square spade or trenching shovel makes quick work of this; a trowel works fine for shorter runs.

If you’re working around a corner, mark the inside and outside curves separately. For tight bends, one source advises bending the edging with pliers after placing it — do that slowly to avoid kinking the metal.

Set, Join, and Stake in the Right Order

Place the edging in the trench with the top edge at or just above finished grade — think about where the grass line will sit after backfill. Overlap the ends according to your manufacturer’s guidance: some products call for 2–3 inches of overlap, others for 4–6 inches. The Home Depot install sheet specifies 2–3 inch overlaps secured with zip ties or metal clips for their corrugated edging. Whatever the overlap, do not force a tight fit on long runs — leave a small gap at connectors so thermal expansion doesn’t buckle the metal on hot days.

Drive stakes through the predrilled holes or tabs using a rubber mallet. Space them every 18–24 inches, closer on curves to maintain the shape. If the product lacks holes at a critical point, drill one — never stake through the face of the edging, which can deform it. And don’t try to bury the stakes with a steel hammer. Use a rubber mallet (or a scrap block of wood between the stake and a regular hammer) to avoid bending thin metal.

Backfill, Compact, and Check Your Grade

This is where most installations fail. Push soil back into the trench on both sides of the edging and tamp it firm with your hand, a small tamper, or the back of a shovel. The top edge should not move when you push it. If it tilts, you haven’t compacted enough. Pack soil right up to — but not over — the top edge of the metal. Once it’s locked, water the backfill lightly, let it settle, and add a final thin layer of soil or mulch to hide the disturbed earth.

Common Mistakes and How to Skip Them

• Skipping the layout. Buying edging by guessing the length is the most expensive mistake. Measure twice, mark once.
• Using the wrong cutting tool. Corrugated metal edging calls for tin snips or a utility knife, not a hacksaw or angle grinder, which can warp or burn the edges.
• Overdriving the stakes. Once the stake top is flush with the edging, stop. Driving deeper can dimple the metal and create a weak spot.
• Ignoring thermal gaps. On long straight runs, leave a tiny space at connectors so heat expansion doesn’t lift the line.
• Not compacting. Loose backfill guarantees a tilted edge after the first hard rain. Tamp it firmly before you call the job done.