Hedge Planting Calculator & Spacing

What Goes Into the Numbers

This calculator divides the hedge length by the plant spacing to find how many plants fit in a single row, then adds one for the plant at the starting end. If you select a double row, the total doubles — the second row runs parallel with plants staggered between those in the first row. The extra plants percentage covers failures during establishment. Bare-root plants have a 5–10% failure rate in the first year, so 10% extra is the standard buffer.

Spacing varies by species. Fast-growing privet needs tight spacing at 300mm for a dense screen within 2–3 years. Slower species like yew and beech use 450–600mm because their mature spread fills the wider gaps. Laurel, the widest hedging plant, spaces at 600–900mm. Double rows create thicker hedges faster but use twice the plants — they are most common for beech and hornbeam where a solid screen is wanted from the base. For area-based planting in beds rather than linear hedges, use the grid and staggered layout tool instead.

Making Sense of the Output

Three outputs appear: plants per row, total plants needed (single or double row with extras), and hedge length confirmed. The plants-per-row figure tells you the spacing intervals along the row. For double rows, the total is twice the per-row count plus the extra percentage.

Use the total when placing your nursery order. Most hedging suppliers sell in bundles of 10 or 25, so round up to the next bundle size. The few spare plants from rounding are useful replacements if any fail in the first winter.

Practical Tips for Planting

The planting season matters more for hedging than for most garden plants. Bare-root hedging (the cheapest option by far) must be planted between November and March while dormant. Pot-grown plants can go in year-round but cost 3–5 times more per plant. For a 10-metre privet hedge at 300mm spacing needing 38 plants, bare-root whips cost roughly £0.50–£1.50 each (£19–£57 total), while pot-grown plants cost £3–£8 each (£114–£304).

Dig a trench rather than individual holes — a trench 300mm wide and 300mm deep gives roots space to spread laterally along the hedge line. You may need to calculate topsoil volumes if the excavated soil is poor and needs replacing. Mix excavated soil with compost at a 3:1 ratio and backfill around the roots. For double rows, dig the trench 600–700mm wide to accommodate both rows with 400mm between row centres. Stagger the plants so each one in the second row sits between two plants in the first row, creating a zigzag pattern.

Water bare-root plants in immediately after planting and apply a 50–75mm layer of bark mulch along the trench to retain moisture and suppress competing weeds. Avoid planting in frozen or waterlogged ground. Trim the top third off bare-root whips at planting to encourage bushier growth from the base — this feels counterintuitive but produces a denser hedge from year one.

Real-World Adjustments

Reduce spacing by 50mm for exposed or windy sites where a denser hedge is needed for wind filtering. For formal hedges that will be trimmed twice yearly, tighter spacing gives a smoother finished surface. Informal hedges (beech, hornbeam) that are trimmed once in late summer can use the wider end of the species range. The linear-measurement logic here mirrors how skirting board lengths are calculated for interior rooms.

If planting next to a boundary fence, check your legal obligations — hedge plants must be positioned entirely within your property, including the root spread. The Anti-social Behaviour Act 2003 covers hedge height disputes between neighbours, so it pays to plan the mature dimensions before planting. If you are laying a paved path alongside the hedge, allow 300mm clearance from the trench edge to prevent root disturbance.