Ask ten robot mower owners what tripped them up, and most will point at the wire. Not because it is hard, but because a few small habits make the difference between a perimeter that just works and one you re-peg every weekend. I have laid wire on tidy rectangles and on lawns shaped like a jigsaw piece, and the same rules held every time. Consistent gaps, gentle corners, and firm pegging do almost all the work. Follow the order below and you can circle an average yard in an afternoon, then forget the wire ever existed once the grass grows over it.

Plan the Route Before You Peg a Thing

Walk the whole lawn first with the spool in hand and picture the loop. The wire starts at the dock, traces the entire perimeter, and returns to the dock, so it must form one unbroken circle. Decide where it hugs the edge and where it swings inward around a bed or a tree. Islands like a flower bed in the middle of the lawn need the wire to run out, loop the island, and run back along the same line. Sketching the route on a photo of your yard for five minutes saves you from unspooling wire you later have to pull up.

New to this? Start with our overview, How to Install a Robot Lawn Mower Step by Step, then come back here.

Set the Right Gap From Edges and Obstacles

The mower reads the wire and turns before it reaches it, so the gap you leave decides how close it cuts. Against a solid wall, fence, or bed you want a small buffer, often around a foot, so the body clears the edge without scraping. Where the lawn meets a flush path or driveway at the same height, you can run the wire much closer since the mower can safely overhang. Check your manual for the exact figures, because they vary by model. Keep each gap consistent, since wandering spacing is what leaves ragged uncut strips along the border.

Boundary wire held down by a peg along a neat lawn edge in a garden

Peg It Down So It Stays Down

Lay the wire flat on the grass and drive a peg every two to three feet, closer on curves where it wants to lift. On straight runs you can stretch the spacing a little, but never let the wire bow up between pegs, because a loop sticking up gets caught by the blades or a mower wheel. Press each peg fully flush so a lawnmower or a passing shoe never catches it. Within two to three weeks the grass grows through and over the wire, hiding it completely and locking it in place better than the pegs alone.

Mind Buried Utilities: Before you dig a trench to bury the wire, know where irrigation lines, low-voltage lighting cables, and utility runs sit. Slicing an unseen pipe turns a simple afternoon into an expensive repair. Pegging on the surface avoids the risk entirely, and the grass hides the wire within a few weeks anyway.

Handle Corners and Curves Cleanly

Sharp ninety-degree corners are where mowers most often lose the line or clip the bed. Instead of a hard right angle, ease the wire around a slight curve using several close pegs. On tight inside corners, a gently rounded path lets the mower turn smoothly rather than jabbing at the point. Long sweeping curves need extra pegs too, since the wire naturally wants to spring back to a straight line. Take these bends slowly. Five extra minutes and a handful of pegs on the awkward corners will spare you a season of the mower nosing into a flower bed.

Boundary Wire Do's and Don'ts

  • Do plan the full loop before unspooling any wire
  • Do keep a consistent gap from beds, walls, and fences
  • Do run the wire close to flush paths the mower can overhang
  • Do peg every two to three feet, tighter on curves
  • Do round off sharp corners with several close pegs
  • Do press every peg fully flush with the soil
  • Don't leave the wire bowing up between pegs
  • Don't cross the two wires or twist them together
  • Don't cut the loop short before you reach the dock
  • Don't reverse the ends at the dock terminals
  • Don't rush corners, since that is where problems start
  • Don't bury the wire until a test run proves the route works

This connects neatly with Installing a Robot Mower on a Sloped Lawn.

Connect the Ends and Power the Dock

Bring both wire ends back to the dock and strip them only if the connectors require it, though many kits use gel-filled clips that pierce the insulation for you. Match each end to its labeled terminal, since reversing them can confuse the signal. Snug the connections and tuck the last stretch of wire neatly under a peg so nothing dangles. Power up the dock and look for the steady status light that confirms the loop is complete and carrying a signal. A blinking or error light almost always means a loose connector or a break, not a faulty mower.

Boundary wire ends connected to the terminals of a robot mower charging dock

It is worth skimming the basics of robotic mower navigation for extra context.

Test the Loop and Fix Weak Spots

With the signal live, send the mower on a boundary-follow run if your model offers one, or just watch a normal cycle. Trace its path around the whole perimeter and mark any spot where it crosses the wire, hesitates, or leaves an uncut band. Crossing usually means the wire sits too far in or a corner is too sharp, so nudge that section and re-peg. An uncut strip means the gap is too generous there. Small adjustments now, while the wire still lifts easily, are far quicker than digging it out after the grass has grown over it.

The short version

A boundary wire only feels fiddly until you understand what it is asking for: one clean, unbroken loop with steady gaps and no loops popping up to snag a blade. Plan the route, keep your spacing honest, ease around corners, and prove the whole thing with a test run before you commit to burying anything. Wire done this way disappears into the lawn within a few weeks and quietly does its job for years. Treat the awkward corners with a little patience today, and your mower will trace the same tidy edge long after you have forgotten the wire is even there.

For a closer look, see How Far to Keep Boundary Wire From Obstacles.