Cutting Back Leylandii: How Far You Can Go and When
How to cut back or reduce a leylandii hedge in the UK without leaving brown bare patches, the right time of year, and when to hire help or replace it.
Leylandii grow fast, often a metre or more a year, and can quickly turn from a tidy screen into a wall that blocks light and annoys neighbours. The most important thing to know about cutting them is that they usually do not regrow from old bare wood.
The golden rule
Conifers like leylandii only produce new shoots from the green, leafy growth. If you cut back into the brown, leafless interior, those cuts are unlikely to produce new foliage, leaving permanent brown or bare patches. So always keep your cuts within the green.
That means regular trimming is the best approach. A hedge that is cut lightly once or twice a year stays manageable. One that has been left for ten years cannot easily be taken back by half.
When to cut
- Late spring to late summer: typically from May to August, but check for nesting birds first. See when you can trim hedges.
- Early autumn: a final light trim in September can tidy for the winter.
- Avoid hard frost and drought, which stress the plant, and avoid very hot sun that scorches freshly exposed foliage.
How to trim a leylandii hedge
- Check for nests and plan your route.
- Set up safely. Use a stable platform or tower rather than a ladder where possible. Do not stretch.
- Cut the sides first, working from bottom to top, shaping a slight taper so the base is wider than the top. This lets light reach the lower branches.
- Trim lightly, removing the new growth only.
- Cut the top to the desired height, again within the green.
- Rake up clippings from the ground and the base of the hedge, and compost or dispose of them; see garden waste disposal in the UK.
If it is already too tall
If the hedge is much taller than you want, you have limited options:
- Reduce the height gradually over a few seasons, taking a bit off the top each year while keeping the cut within the green.
- Cut the top out and accept a flatter profile, but only if there is green growth close to the cut.
- Take it out and replace it with a different hedge, fence or planting. This is often the best choice if the hedge is a lot too big, has gaps or is brown at the base.
Remember that cutting a very tall hedge is high-risk work. Ladders, powered cutters and heavy waste are a hazardous combination, and an experienced professional with proper access equipment is a safer choice. See hedge trimming cost in the UK for typical prices.
Neighbours and the law
In England and Wales, high hedges of evergreen trees over two metres that block light to a neighbouring home can be the subject of a complaint to the local council. This is generally a last resort, and speaking to your neighbour first is usually better. If you are on the receiving end, keeping the hedge trimmed to a reasonable height shows goodwill and avoids formal action.
Aftercare
- Water after cutting in dry weather.
- Feed lightly in spring with a general fertiliser, if the hedge looks pale.
- Keep the base clear of weeds and leaf litter.
- Do not cut too hard in one go.
Replacement options
If you decide to remove the hedge, you will need to deal with roots and stumps; see stump grinding cost. Alternatives include beech, hornbeam, yew or a mixed native hedge, which give screening with a gentler growth habit.
Finding help
On Compito you can search by postcode, compare ID-verified local providers and send a request with photos, length and approximate height. You can message them to confirm the method and waste handling before you accept an offer and pay online. See how it works.
Worked example: a hedge left for five years
A 15m leylandii hedge has reached around four metres and a metre wide at the top. The owner wants it at two and a half metres. Cutting the top now would expose brown wood and leave a bare, permanently ugly flat top. A better plan: reduce the width of the sides lightly, keeping within the green, in the first year; take a small amount off the top each year; or have the hedge assessed for replacement. Many owners find that after a couple of years of trying to rescue a hedge like this, replacement is neater, and often cheaper than repeated attempts.
How much can you take off?
| Situation | What is realistic |
|---|---|
| Regularly trimmed hedge | Light trim of this year's growth |
| Left a couple of years | Modest reduction while staying in the green |
| Left five years or more | Likely too large; consider replacement |
| Brown or bare base | Cutting will not restore it |
| Very tall (over around three metres) | Specialist access and safety needed |
Checking where the green ends
Part the outer foliage and look inside. If you can see green shoots close to the cut line, you have room. If the next layer in is bare brown wood, stop. Photograph the hedge from a few angles and use the photos when asking for quotes.
Safety and who should do it
Leylandii grow tall and the clippings are heavy. Use a stable tower or platform, not a leaning ladder, and never work near power lines. Anything above comfortable reach from the ground is a job for qualified professionals, and a tree surgeon may be more appropriate than a gardener for a very tall hedge; see tree surgeon vs gardener.
Talking to neighbours
If the hedge is on a boundary, tell your neighbour before the work starts, as it will change their light, privacy and view. Agree who deals with clippings on each side to avoid disputes.
Frequently asked questions
Will leylandii grow back if I cut it hard?
Usually not from bare brown wood. Cutting back to leafy green growth is the only reliable way to keep a good-looking hedge.
How often should I trim it?
Typically once or twice a year, depending on growth and how formal you want it. Little and often is better than occasional big cuts.
Is it better to remove an overgrown leylandii hedge?
Often, yes, if it is much too big or brown at the base. Replacement can be cheaper and safer than repeated attempts to tame it.