Why hedge spacing needs its own calculator
A hedge is a linear planting problem, not a plants-per-square-metre problem. The important inputs are the length of each run, the spacing along each row and the number of rows. Gates and separate sections matter because each run has its own start and end.
Endpoint handling: the off-by-one problem
If a 10 m run is planted at 50 cm centres, a simple density approach gives 20 plants in a single row. Those 20 plants can be positioned with the first and last plant inset from the two ends. If the design instead requires a plant at both exact endpoints, 10 m contains 20 intervals of 50 cm, so it needs 21 plants. The calculator exposes this choice rather than hiding it.
Published spacing varies — and that is useful information
RHS hedge advice says within-row spacing commonly varies from roughly 30–60 cm depending on final size, hedge size and plant vigour, while its plant-selection table gives different spacing codes for different hedging plants. Woodland Trust guidance for native hedge planting gives a 30 cm single-row example and a denser zig-zag double-row approach. Specialist nurseries publish still other values for particular stock and species.
Those figures should not be averaged into one supposedly “correct” setting. Use the value attached to the actual hedge plants you plan to buy, then let this calculator handle the quantity.
Multiple runs, corners, gates and gaps
Measure separate hedge sections independently. If a gate splits a boundary into a 6 m run and a 4 m run, add both runs to the calculator rather than entering 10 m and hoping the endpoint count still works. The same principle applies to driveways or deliberate access gaps. A corner can be treated as one continuous run only when the planting pattern truly continues around it.
Single vs staggered double rows
A staggered double row is used to create a broader, denser hedge, but it is not appropriate for every plant or site. The spacing along each row and the gap between rows both come from the planting specification. The calculator asks for the row gap so the pattern can be planned, but correctly keeps it separate from the in-row plant count.
Common hedge-ordering mistakes
- Using a universal “plants per metre” figure without checking the species and stock being purchased.
- Forgetting that a design with plants at both exact endpoints can need one more plant than a simple length ÷ spacing calculation.
- Counting across a gate or driveway as though the hedge were continuous.
- Doubling a single-row number without understanding the spacing specified for an actual staggered double row.
- Using mature hedge width as the in-row plant spacing without checking supplier planting guidance.
RHS hedge planting guidance explains that spacing varies with final size and vigour. Woodland Trust hedge guidance provides single- and double-row native hedge examples. Specialist nursery guidance, such as Ashridge Nurseries, demonstrates that plants-per-metre recommendations differ by hedge type.
Useful next step
Read the Hedge Spacing Guide before ordering if you are still choosing between single and double rows or comparing different supplier recommendations.