Landscape timber edging is easy to install and creates an attractive, natural-looking frame for a flower border or perennial flower bed. You can also use it to line areas of grass. It's much more substantial and attractive than galvanized metal edging, and it will hold up better than plastic. Compared to stone or concrete edging blocks, timbers are less expensive and much quicker to install.
The trick to installing timber edging is getting the ground flat and the edging path straight. Wood doesn't easily bend or dip to conform to ground contours. To turn corners with wood edging, you must fit the timbers together at an angle, much like with baseboard trim inside your house. To make a 90-degree turn, you can simply butt the square ends of timbers together, but any other angle requires a miter cut; this is easy once you know how to do it.
Landscape timbers come in a few different shapes. Some are square-edged, like a fence post; some are almost oval in shape and have two wide flat sides and two narrow rounded sides; some have rounded sides but are more square in overall dimension; and some have square bottom edges and a rounded top. All landscape timbers should be pressure-treated to prevent premature rot due to ground contact.
Equipment / Tools
- Mason's line or string
- Hand sledge or hammer
- Hand edger
- Garden hoe or steel rake
- Level or straight board
- Tape measure
- Drill and bits
- Landscape timbers
- Landscape fabric and staples (optional)
- Galvanized corner braces
- Galvanized mending plates
- 2-inch galvanized deck screws
- #3 rebar (optional)
Mark the Border Path
Tie one end of a mason's line around a stake. Drive the stake into the ground at one end of the border planting or grass area. Walk to the other end of the border planting, then tie the string to another stake. Pull the string taut and line it up exactly where you want the edging to run, then drive the second stake into the ground.
Cut Through the Turf
Use a hand edger or a flat spade to slice through the turf or other plantings just under the string, starting at one end and working to the other end. Remove the turf with a shovel. You can transplant healthy turf to another area; otherwise, shake off as much soil as possible from the roots (to make the turf much lighter) and compost or discard the grass plants. Remove all weeds and other organic material from the bed area.
Level and Tamp the Ground
Prepare the ground at the edge of the border planting so that it is ready to receive the landscape timber edging. Use a shovel, a steel rake, or a garden hoe to dig out rocks, roots, and other obstructions along the edging's path.
Walk over the loosened soil to pack it down. Add soil, as needed, to bring the area up to the proper level, then pack it down again. Make sure the soil is firmly packed to prevent settling.
Check for level as you go, using a carpenter's level or a straight board. The ground does not have to be exactly level according to a level; it must be flat and level with the surrounding area.
Add Landscape Fabric (optional)
Install landscape fabric, if desired, to prevent weed and grass growth. This is a good idea if the bed or other area beyond the edging will be covered with rock, mulch, or other ground cover. Roll out the fabric over the soil and position it so it is even with the mason's line; you will install the timbers on top of the fabric. Secure the fabric with landscape fabric staples driven with a hand sledge or hammer.
Install the Timbers
Lay out straight timbers along the full length of the edging, butting their ends together. If the final straight piece will be shorter than about 2 feet, shift the entire row of timbers so that the two ends will have cut pieces of roughly equal length.
Position the full-length timbers accurately along the edging line. Join neighboring timbers with pairs of galvanized mending plates and 2-inch deck screws. Drive the screws with a drill fitted with a screwdriver bit. If the screws are difficult to drive, drill pilot holes before installing the screws.
When you reach one end of the edging run, mark the last piece for cutting at the desired length. Cut the marked timber to length, using a miter saw, if you have one; otherwise, you can use a hand saw or a reciprocating saw. Join the cut piece to the end of the row with mending plates, as before. Repeat the same process at the other end of the straight row.
Construct the Corners
Cut more straight pieces, as needed, to make 90-degree turns. Join the pieces at each corner with a galvanized corner brace and screws, as with the mending plates. The braces should be on the inside of the corners.
Cut Angles to Make Turns
Use a protractor to lay out angle cuts for turns in your edging that are not 90 degrees. Place the protractor on top of the timber and align the protractor's base line with the edge of the timber. Mark the edge of the timber at the protractor's center mark. Determine the desired angle for the completed turn, divide that angle in half, then mark the timber along the top of the protractor at the resulting angle.
For example, if the edging will turn at 120 degrees (forming an obtuse angle), mark the top of the timber at the 60-degree line on the protractor. Finally, draw a straight line through the 60-degree mark and the center mark to create an angled cutting line. Cut the timber along the line.
Repeat the same process to mark and cut the mating timber so that each is cut at 60 degrees (and the two angles face opposite directions). When you fit the angled ends together, they will make a 120-degree turn. You can secure the pieces together with screws driven at an angle through both pieces (drill pilot holes first), or you can bend a 90-degree corner brace to match the custom angle, and install the brace with screws.
Pin the Timbers With Rebar (optional)
Secure the timber border to the ground with rebar, if desired. Drill 3/8-inch holes through the centers of the timbers, spacing the holes about 4 feet apart. Pin the timbers to the soil with 12-inch lengths of #3 (3/8-inch-diameter) rebar driven with a hand sledge. Drive the rebar flush with the timber face, then use an extra piece of rebar as a punch to drive the installed rebar slightly below the wood surface (for safety reasons, you don't want any metal sticking up above the wood). Note: Be careful not to drive rebar anywhere there may be underground sprinkler lines.
Fabric and Mulches for Weed Management in the Landscape. University of California University of Agriculture and Natural Resources.