How to Install Bender Board Landscape Edging? | Straight Curves Every Time

Installing bender board landscape edging means digging a trench, setting the board so 75% or more is buried, and driving galvanized stakes every 24 inches with screws to hold it in place.

Bender board is a flexible plastic composite that bends around tight curves and holds its shape year after year—but only if installed right. The most common mistake is leaving too much board above the soil line, which leads to sagging and frost heave. Fix: bury at least 80% of the board’s height.

What You Need Before You Dig

You don’t need many tools. Standard rolls are 20 feet long in 4-inch or 6-inch heights. “4-inch” boards actually measure about 3.5 inches tall, and “6-inch” boards run 5.5 inches—account for real height when planning trench depth. Plan on 4 to 5 stakes per roll for straight runs; double that for tight curves.

• Tools: sharp flat spade or power edger, hand sledge (or regular hammer in soft soil), garden hose for layout, chalk or landscape marking paint
• Stakes: galvanized or composite, 12-inch minimum length
• Fasteners: number 6 galvanized or coated screws, 1-inch length
• Prep step: call 811 at least two business days before digging to mark underground utilities

The Step-by-Step Installation Sequence

1. Plan and Mark Your Layout

Lay a garden hose or rope to define curves before trenching. For straight lines, use string stretched between stakes. Trace with powdered chalk or landscape paint. Don’t skip this step—filling and re-digging is twice the work.

2. Prepare the Ground and Dig the Trench

Clear rocks, grass, roots, and debris. Wet the area lightly to soften soil.

3. Install the Bender Board

Lay the board in the sun for a couple hours to soften. Place it into the trench and check it sits flush. Drive stakes every 24 inches for straight sections, every 12 inches for tight curves. Hammer each stake so its top sits about 1 inch below the board’s top edge—hiding the stake after backfilling. For sweeping curves, drive stakes on the inside of the arc for outward tension. Use double stakes at joints.

4. Secure and Join Sections

Drive two 1-inch galvanized screws through each stake into the board. When connecting two lengths, overlap ends by at least 4 inches and screw through both into a single stake. Leave a small expansion gap (eighth-inch) at every joint to prevent buckling on hot days.

5. Backfill and Finish

Pour soil or decorative rock against both sides simultaneously—filling one side first pushes the board out of alignment. Tamp firmly with a hand tamper or boot heel to eliminate air pockets. Taper the top two inches of soil on the garden side to accommodate mulch without spilling.

For product comparisons, see our tested roundup of the best bender board landscape edging options.

Common Mistakes That Cause Problems Later

• Too much board above grade: leaving more than 25% exposed leads to sagging and frost heave. Bury 75–80%.
• Stakes too far apart: 24 inches is the maximum for straight runs.
• Visible stake tops: hammer them 1 inch below the board’s top.
• No expansion gap: tight joints buckle in summer heat.
• Sharp kinks in curves: force bends without sun-softening causes stress cracks.

How Deep Should the Trench Be?