Landscape timbers add an attractive, natural-looking frame for a flower border, perennial bed, or lawn edge. The project is straightforward enough for a beginner, takes about eight hours from start to finish, and runs about one dollar per linear foot in materials. For that price you get a defined edge that keeps mulch in place and grass out of the bed. Timber edging relies on the same material family that carries heavier loads elsewhere: pressure-treated lumber is a form of structural timber, engineered for contact with soil and moisture.
All landscape timbers should be ground-contact rated and pressure-treated to prevent premature rot. That rating matters because the bottom course sits against damp soil for years, and untreated wood fails within a season or two. With the right material and a few hours of work, a timber border lasts a decade or more with minimal upkeep.
Planning the Project and Gathering Materials
Measure the border before buying anything. Run a tape measure along the planned edge, add ten percent for cuts and waste, and decide how tall the border should be. One course of timbers gives a low, neat lip; two stacked courses hold back more soil and create a raised bed. Homeowners weighing options often compare timber against concrete edging, which lasts longer but costs more and demands more skill to place, so the choice usually comes down to budget, tool access, and how permanent the edge needs to be.
| Factor | Timber edging | Concrete edging |
|---|---|---|
| Material cost | About $1 per linear foot | $3 to $8 per linear foot |
| Lifespan | 10 to 15 years with ground-contact treatment | 30 years or more |
| Skill level | Beginner | Intermediate to advanced |
| Appearance | Warm, natural | Clean, structural |
| Repair | Replace individual timbers | Patch or replace whole sections |
Tools and Materials Checklist
Everything on the list is available at a hardware store, and most homeowners already own part of it. For layout you need stakes, mason’s line or string, a hand sledge or hammer, a hand edger, a shovel, and a garden hoe or steel rake. For the build itself you need a level or straight board, tape measure, pencil, saw, and a drill with bits. The materials list is short: ground-contact pressure-treated landscape timbers, landscape fabric and staples if you want a weed barrier, galvanized corner braces, galvanized mending plates, 2-inch galvanized deck screws, and #3 rebar if you plan to pin the border down.
Estimating Quantity and Choosing Timber
Timbers come in 8-foot lengths and standard cross sections of roughly 4 by 6 inches or 6 by 6 inches. Divide the border length by 8 to estimate the number of pieces, then round up. Pick pieces that are straight and free of large splits, because bowed timbers fight the layout at every corner.
Estimating How Many Timbers
A 20-foot border needs three 8-foot timbers for the first course after cutting, and a double-course border needs six. Add one spare for mistakes and warped pieces. Timbers are sold by the piece, so round your estimate up to the nearest whole length and buy the spare.
Marking the Border Path
Layout decides everything that follows, and a clean line comes from two stakes and a taut string, the same method used in any landscape edging project. It takes five minutes to set up. Tie one end of a mason’s line around a stake, drive the stake into the ground at one end of the border, walk to the other end, pull the string taut exactly where the edging should run, and drive the second stake. The string now marks the outside face of the border, and every cut follows it.
Setting Stakes and String
- Drive the first stake at one end of the planned border.
- Tie the mason’s line to the stake and run it to the far end.
- Pull the line taut and line it up with the exact edge position.
- Drive the second stake and recheck the line by eye from both ends.
Square Corners and Gentle Curves
For a corner, hold the string at 90 degrees and check with a framing square or protractor. For a curve, set extra stakes every few feet along the arc and bend the string around them. Straight runs hide small errors; curves amplify them, so take the extra minute to set the arc before digging.
Cutting the Turf and Preparing the Trench
Once the line is set, cut through the turf along it with a hand edger. The cut gives a clean vertical face that holds the timbers and stops grass from creeping under the border. After cutting, remove the sod strip with a shovel and dig a shallow trench about two inches deep and as wide as the timber. The bottom course sits in the trench, which keeps the border from shifting sideways as the soil settles. What goes under the timbers matters as much as the timbers themselves. Advanced construction materials such as fiber-reinforced polymers and mass timber changed how builders think about durability, and the lesson applies at garden scale: a fabric barrier and gravel base extend the life of wood edging.
Digging the Trench
- Cut the turf with the hand edger along both sides of the string.
- Roll back or remove the sod strip with a shovel.
- Dig the trench to a consistent two-inch depth across the run.
- Tamp the bottom with the back of a hoe or a hand tamper.
Adding a Base Layer
Lay landscape fabric in the trench and staple the edges, then add an inch of crushed gravel or sand. The fabric blocks weeds and grass, and the gravel gives the timbers a level, well-drained seat. Skip this step and the border will rock and heave as the soil underneath shifts.
Installing the Timbers
Lay the first course end to end in the trench, butting the pieces together. Stagger the joints between courses the way masonry staggers its bonds, so no two joints line up. Where the border turns, mark the angle with a protractor or speed square and cut the timber with a saw. Straight runs are simple; bends and curves need the same joinery thinking that goes into curved timber techniques in timber frame construction, where each piece is cut to match the arc before anything is fastened.
Securing the Border
Drive #3 rebar through pre-drilled holes at each joint, two per timber, so the pins go deep into the soil below. At corners and butt joints, add galvanized corner braces and mending plates with 2-inch galvanized deck screws. Galvanized hardware resists corrosion in damp soil, so the fasteners last as long as the wood.
Stacking a Second Course
For a raised bed, stack a second course on top and screw the layers together from below or through pre-drilled countersunk holes. Stagger the end joints against the course below, and check each piece with a level before driving screws.
Finishing and Backfilling
Backfill behind the finished border with soil, working it into the gap with a garden hoe, then compact it with your foot or a tamper. Water the backfill to settle it, and top off any low spots after a day. Mulch inside the bed so the border reads as a clean frame rather than a buried row of wood. Engineered wood products such as cross-laminated timber in tall buildings proved that wood can carry loads once reserved for steel and concrete, and a well-anchored timber border uses the same principle in miniature, holding soil in place season after season.
Cleaning Up the Edge
Cut any turf that hangs over the timber with the hand edger, sweep the top of the border clean, and treat the ends of cut pieces with wood preservative if the cut exposed untreated heartwood.
Maintaining the Border
- Check joints and fasteners each spring; retighten screws that have backed out.
- Refill low spots behind the border after heavy rain.
- Rinse or brush moss and algae off the timber faces so the surface does not get slick.
When to Call a Pro and When to Replace
Most borders are a weekend DIY project, but some situations justify a professional: long runs with many angles, borders on steep slopes, or ground that needs grading before the timbers can sit level. A pro also makes sense when the project is part of a larger hardscape plan. Even with good material, a border eventually wears out. The grading and engineering behind scalable timber engineering, from LVL to CLT mass timber systems in mixed-use buildings, exists because wood fails predictably when it is protected; the same care keeps a garden border working for a decade or more.
Signs It Is Time to Replace
- Rot that extends more than an inch into the timber or crumbles under a screwdriver.
- Cracks wide enough to let soil and water into the core.
- Heaving that lifts the border out of level after repeated freeze-thaw cycles.
- Termite or carpenter ant damage in the bottom course.
Replacing a section follows the same process as the original install: pull the damaged timber, re-level the base, and set the new piece. A border maintained this way stays tidy for years.