How to Plant Hedges | Get the Spacing Right the First Time

Getting a hedge established comes down to a handful of steps done right. Most failures trace back to planting too deep, skipping the string line, or spacing plants too far apart. This guide walks through the strip prep, the spacing math, and the aftercare that carries a new hedge through its first year.

Prepare the Planting Strip

Hedges grow best when they don’t have to fight for water and light from day one. The RHS recommends digging over a strip 60–90 cm wide and one spit deep, removing weeds and roots as you go. Skip the chemical weed control here — the RHS advises non-chemical methods instead, since herbicides can linger in soil and damage young roots.

If you’re planting a boundary hedge, set it back about 90 cm from the property line. That gap keeps the hedge off the neighbor’s side and gives it room to fill out. Wet, winter-waterlogged soil needs drainage work or a raised ridge before anything goes in the ground.

Lay Out the Line and Set Spacing

A string line pulled taut between two stakes is the difference between a straight hedge and a wavy one. Both the RHS and the Woodland Trust recommend setting plants out along the line before digging any holes — that way you can adjust spacing while everything is still easy to move.

Spacing depends on the hedge’s final job:

• Single-row hedge: 30–60 cm apart, depending on plant size and how dense you want the screen
• Thicker hedge (over 90 cm wide): staggered double row, plants 90 cm apart with rows 45 cm apart
• Woodland Trust’s rule: roughly 30 cm spacing in a single row, or 30–40 cm gaps in a zig-zag double row at five plants per metre

Too-wide spacing is the most common hedge mistake — it delays filling in by years. When in doubt, check the mature spread of the species you chose and work backward from there.

Plant at the Right Depth and Backfill

Depth errors kill more new hedges than anything else. Plants should sit at the same depth they grew at in the nursery, with the root flare level with the surrounding soil. Container-grown plants often have the top of the root ball covered in compost — scrape it down gently until you find that flare before planting.

Set each plant in its hole, then work soil in among the roots as you backfill. Firm the soil with your heel so it makes solid contact with the root system — air pockets dry out roots and slow establishment. Trim any damaged or circling roots back to healthy growth with sharp secateurs first. In sandy or heavy clay soil, mix compost or a proprietary tree-and-shrub planting mix into the backfill or the top 25 cm of soil.

When the hole is filled, water thoroughly. Then add a generous mulch to a depth of about 7.5 cm to hold moisture and suppress weeds. If you’re looking at the best shrubs and hedges for your yard, check their mature size before you set spacing — vigor varies a lot between species.

Aftercare in the First Year

The Woodland Trust recommends letting a new hedge establish for at least a year before any serious trimming. During that first growing season, water extra — one common schedule is twice weekly for the first eight weeks. A hedge planting guide from the RHS covers this establishment phase in detail.

In the following spring, cut shrubs back to about 60 cm tall, just above a bud, to encourage bushiness from the base. Wait another two years after that before regular trimming.

Common Mistakes to Avoid

• Planting too deeply — the root flare must stay at soil level, never buried
• Skipping the string line — a crooked hedge is permanent without major rework
• Spacing too wide — delays filling in and leaves gaps for years
• No mulch or water after planting — increases stress and weed competition
• Ignoring damaged roots — circling or broken roots strangle the plant later

Get these basics right and your hedge will settle in fast. The strip prep, the spacing, and that first year of water are where the whole job is won.