Short answer
For a lawn edge, buy steel strip at least 4 inches tall, bury it so only about 1/2 to 1 inch shows, and stake it on the bed side. 14 gauge is the light residential weight; 1/8 to 3/16 inch steel holds a straighter line over long runs. Pick a powder-coated finish for black or brown, or plain steel if you want it to weather. If people walk barefoot nearby, choose a rolled top or a vinyl cap.
Why choose metal edging
A steel strip shows as a thin line, so the lawn and the bed meet without a visible border. It goes deep enough to stop most grass runners, it holds curves, and it stands up to mowers. University of Illinois Extension calls steel the edging that lasts longest, while noting it is relatively expensive, harder to install well, and can heave in frost if it is not anchored.
Metal is also the go-to edge for gravel paths and rock beds, where a rigid line keeps the stone from spreading. For those jobs, see edging for gravel and mulch.
Thickness: gauge and plate
| Thickness | What it is like | Good for |
|---|---|---|
| 14 gauge | The light residential weight. Bends by hand into curves. | Flower beds, gentle curves, DIY |
| 12 gauge | A step stiffer. Holds a straighter line. | Lawn edges with long runs |
| 1/8 to 3/16 in | Plate weight. Very straight, resists dents. | Gravel paths, commercial-looking lines |
| 1/4 in and up | Heavy plate. Hard to curve without tools. | Raised edges, driveways, pro installs |
Colmet lists its steel edging from 14 gauge through 12 gauge, 1/8, 3/16, 1/4 and 3/8 inch, in 4, 5, 6 and 8 inch heights and 10 foot lengths (maker specs). Other makers use similar steps. Check the actual thickness on the listing, because some sellers say "heavy duty" without giving a gauge.
Height: how tall a strip to buy
- 4 inch: the common size for beds and lawn edges. Buried with about 1/2 to 1 inch showing, that leaves roughly 3 inches in the soil.
- 5 to 6 inch: more depth against spreading grass, or more height above a gravel or mulch bed.
- 8 inch: for aggressive roots or a small step in grade. Edge Right sells an 8 inch strip and says most metal edging is installed 4 to 6 inches into the ground (maker claim).
The full depth rules are in how deep to install landscape edging.
Types of metal edging
-
01Most common
Powder-coated steel strip
Best for: lawn edges and flower beds where you want a thin black or brown line
- Thickness
- 14 ga to 3/16 in
- Height
- 4 to 6 in
- Finish
- Black, brown or green coat
- The coating slows rust and hides the strip against mulch
- Sections join with overlapping tabs or slots
- Scratches in the coat can rust; touch-up paint helps
-
02Curves
Flexible steel edging coil
Best for: beds with tight curves and DIY installs
- Thickness
- Usually light gauge
- Form
- Coil or long strips
- Install
- Narrow trench and stakes
- Thinner steel bends into small radiuses
- Lighter to carry and cut
- Dents more easily than plate weight
-
03Patina
Weathering (Corten) steel
Best for: modern and naturalistic gardens, gravel beds and raised edges
- Finish
- Bare, rusts on purpose
- Height
- 4 in and up
- Watch for
- Early rust runoff
- Forms a protective rust layer instead of a coat
- Can stain pale paving while it weathers
- Full guide: Corten steel edging
-
04Light
Aluminum edging
Best for: DIY installs, coastal yards and long runs you have to carry
- Thickness
- 1/8 or 3/16 in
- Height
- 3 to 5-1/2 in
- Finish
- Mill or coated
- Does not rust
- Lighter than steel
- Full guide: aluminum landscape edging
Finishes
- Powder coat (black, brown, green): the tidy choice for most beds. Colmet lists black, brown and green coats as well as unpainted and galvanized steel (maker specs).
- Galvanized: a zinc coat that resists rust and looks gray.
- Unpainted: rusts to a brown patina over time.
- Weathering steel: made to rust on the surface and then slow down. See the Corten guide.
Installing steel edging
Call 811 and mark the line
Call 811 a few working days ahead so buried lines are marked (Call 811). Lay out the curve with a hose and mark it with spray paint.
Cut a narrow trench
Use a flat spade or half-moon edger to cut a slot just wide enough for the strip and a little deeper than the buried height.
Set the strip
Stand the sections in the slot and join them. Leave about 3/4 to 1 inch above grade, per Gertens, or follow your strip’s instructions.
Stake on the bed side
Drive the stakes on the bed side so they do not show from the lawn. Space them as the maker says; many guides use about every 3 to 5 feet.
Backfill and tamp
Push soil back against both sides and tamp it firm. Water it in so the soil settles, then top up mulch on the bed side.
What you need
The full walkthrough, including no-dig styles, is in how to install landscape edging.
Cost
LawnStarter puts metal edging at about $5 to $11 per linear foot in material, with pro labor adding about $1.50 to $10 per foot. Hunker quotes a wider spread for steel, from under $1 to as much as $15 per foot depending on thickness (Hunker). See landscape edging cost for every material.
Questions people ask
What gauge steel edging should I buy?
For most home beds, 14 gauge steel is the lighter, easier to bend choice, and 1/8 or 3/16 inch steel stays straighter over long runs and resists dents from mowers. Colmet, for example, lists its Traditional edging from 14 gauge up to 3/8 inch. Thicker is stiffer, heavier and harder to curve tightly.
How deep does metal edging go?
Most metal edging goes about 3 to 5 inches into the soil, and a common rule is to leave about 3/4 to 1 inch above grade. Some makers sell 6 and 8 inch tall strips for deeper roots. Follow the product instructions for your strip.
Will steel edging rust?
Plain steel develops a rust patina over time. Powder-coated and galvanized finishes slow that down. Weathering (Corten) steel is made to rust on the surface on purpose. Rust can stain pale paving while the surface is still changing, so keep bare steel a little away from light concrete.
Is metal edging sharp?
The top edge of thin steel strip can cut bare feet or hands. Rolled-top steel and vinyl trim caps soften it. Wear gloves when handling and cutting it.
Is steel or aluminum edging better?
Steel is stiffer and the most durable choice, per University of Illinois Extension, but it is heavy and needs care to install well. Aluminum is lighter, easier to handle and does not rust, but dents more easily and its silver color can look out of place unless it is coated.
Sources
- University of Illinois Extension, Bed edges (Rhonda Ferree, 2015)
- Colmet Traditional steel edging specifications (maker, via Sweets)
- Edge Right, Types of landscape edging: why size and depth matter (maker)
- Call 811, Know what is below (national call-before-you-dig line)
- Gertens, Edging options beyond vinyl (garden center guide)
- LawnStarter, How much does landscape edging cost? (updated December 27, 2025)
- Hunker, The best types of landscape edging
Last reviewed October 12, 2026. Products, sizes and listings change; check the product details before you buy, call 811 before you dig, and follow the maker’s instructions.