Stone edging is the detail that separates a yard that looks maintained from one that looks like it is slowly losing a fight with itself. It holds mulch in, keeps gravel out of the lawn, and gives the mower a clean line to follow. It is also the project most people do wrong in one specific way: they set the stones on top of the soil instead of into it. Difficulty is easy, a 40 ft run takes most of a day, and materials run roughly $6–$20 per linear foot depending on whether you use cobbles, setts, or larger fieldstone.
Tools & Materials
- Edging stone: granite setts, cobbles, wall block, or flat fieldstone
- Crusher run for the compacted setting bed
- Concrete sand or stone dust for fine leveling
- Flat spade and a trenching shovel
- Hand tamper
- Rubber mallet, torpedo level, 4-ft level
- Marking paint or a garden hose for laying out the line
- Angle grinder with diamond blade, if you need cuts
Edging is bought by the linear foot, but the setting bed is bought by volume. Measure the full run, then size material with the stone edging calculator and the crusher run calculator. Add about 10% to the stone count for breakage and for the shorter pieces that tight curves eat up.
Pick the Right Stone for the Job
Granite setts and cobbles are the workhorses — roughly cubic, heavy for their size, and they sit stable in a trench. Flat fieldstone laid on edge looks more natural but needs a deeper trench because a thin stone standing up has almost no resistance to tipping. Concrete wall block is the cheapest and most uniform, and it is the easiest to level, though it reads as manufactured. Whatever you choose, uniform-height stones make a job that goes fast; wildly irregular fieldstone means individually bedding each piece, which roughly doubles the time.
Decide the finished height before you dig. Edging holding back mulch or gravel should stand 2–3 in above the bed surface. Edging you want to mow over should sit flush with the lawn, which means burying more of the stone and building a wider setting bed so it does not sink under the mower wheel.
Pro tip: At least one third of each stone’s height should be below finished grade — half is better for tall or thin stones. Edging that sits on the surface with a little soil pushed against it will tip outward within one freeze-thaw season, no matter how good it looks the day you finish.
Step-by-Step Installation
- Lay out the line with a hose and paint it. Set a garden hose along the intended edge and adjust it until the curves look right from the house and from the street — those are the two views that matter. Keep curves generous; tight radii need lots of small cut pieces and look busy. Paint the line and pull the hose.
- Cut the trench 6–8 in deep and 2 in wider than the stone. Depth is the stone height you want buried, plus 3–4 in for the setting bed. So a 6 in tall sett standing 2 in proud needs about 4 in buried plus 3 in of bed — a 7 in trench. Cut the bed-side wall of the trench clean and vertical with a flat spade; that crisp edge is what makes the finished line look sharp.
- Place and tamp 3 in of crusher run in the trench. Spread it, mist it, and tamp hard with a hand tamper until it stops moving under the plate. Setting stone directly on loose soil is the single most common reason edging goes wavy — soil compresses unevenly under point loads, and every stone settles a different amount. A compacted crusher run bed distributes that load.
- Set the first stone and use it as the height reference. Bed it into a thin layer of concrete sand or stone dust over the crusher run, tap it down with a rubber mallet, and level it front-to-back and side-to-side. Then run a string line from that stone to the far end of the run at finished height. Every subsequent stone gets checked against the string, not against its neighbor — small errors stack up fast when you eyeball stone to stone.
- Work along the run, setting each stone tight to the last. Keep joints as tight as your stone allows; wide gaps let mulch and gravel escape and let weeds in. On curves, fan the joints slightly on the outside of the bend rather than leaving one wide gap, and cut a stone with the grinder where the fan gets larger than about 1/2 in. Tap each stone down to the string, adding or removing bedding sand underneath rather than forcing it with the mallet.
- Backfill both sides and compact. This is the step that makes it permanent. Pack crusher run or soil firmly against the buried portion of the stone on both faces — not just the lawn side — and tamp it in layers. A stone backfilled on one side only is a stone braced against nothing in the direction it will eventually fall. Finish by bringing bed mulch or gravel up to the inside face and lawn soil up to the outside.
Handling Curves, Corners, and Slopes
Curves are where most stone edging jobs come apart visually. The trick is to keep the radius large enough that the stone can follow it with joint fanning alone — as a rough rule, the radius should be at least eight times the length of a single stone. A 6 in sett handles a 4 ft radius comfortably; a 16 in fieldstone on the same curve leaves gaps you cannot close. Where a bed genuinely needs a tight radius, switch to smaller units for that section rather than forcing the large stone.
On a slope, do not tilt the stones to follow the grade. Step the run instead: keep each stone level in itself and drop the setting bed by a fraction of a stone height every few units, so the top edge stairsteps down. Tilted stones shed water along the joint line and slide over time. At corners, set the corner stone first and level it in both directions, then work outward along both legs — a corner built as an afterthought where two runs happen to meet never looks deliberate.
Mistakes to Avoid
- Setting stones on top of grade. Bury at least a third of each stone or it tips out.
- No compacted setting bed. Soil settles unevenly and a straight line becomes a wobble.
- Backfilling one side only. The unsupported face is the direction it will lean.
- Leveling against the previous stone instead of a string. Cumulative drift is invisible until you stand back at the end of a 40 ft run.
- Tight radius curves with large stones. Either use smaller setts on curves or open the radius.
Bottom Line
Stone edging stays where you put it when it is set into the ground rather than onto it: a trench deep enough to bury a third to a half of each stone, 3 in of compacted crusher run beneath, a string line to keep the run true, and firm backfill on both faces. Everything else is stone selection and patience on the curves. Size the run with the stone edging calculator and the bedding with the stone dust calculator. Edging pairs naturally with two other projects on this site — it is what keeps a gravel walkway from spreading, and it is the standard first line of defense described in our guide to stopping gravel migration.
