How to trim a hedge

Always check hedges for nesting birds before trimming them, even out of nesting season, as some such as wood pigeons and house sparrows, will nest all year round if conditions are mild. If growing a native hedge, check blackthorn stems for eggs of the brown hairstreak butterfly before cutting, and leave any you find so they can hatch in spring.

How to trim a hedge

Step one

Lay a tarpaulin on the ground before trimming your hedge to catch the clippings. Make sure your hedge trimmer or shears are clean before you begin. Start by trimming the sides of your hedge, starting at the bottom and moving up to the top. Aim for a hedge that has a narrower top than base. A wider top will shade out the bottom of the hedge and lead to poor growth.

Step two

Put up a string line guide to help keep the top of the hedge straight. Tall bamboo canes and garden string are the easiest way to do this – push canes into the ground, along the length of the hedge, checking they are in line before tying the string along the top.

Step 3

Trim the top of the hedge, cutting to the base of new growth but avoiding cutting into old wood. Do it by eye, standing back to check it's level, or using a string-line guide, as above, just below the top of the hedge. It may be necessary to use a hedge trimming ladder to reach the top if you have a tall hedge.

Step 4

Brush clippings off the top of the hedge and collect any that have fallen on the lawn. These can be added to the compost heap.

How to trim a hedge with shears

Watch our No Fuss video guide to trimming a hedge with shears:

Frequently asked questions

When is hedge trimming season?

The main hedge trimming season is between late summer and autumn, but some hedges may need to be trimmed more than once a year. Evergreen hedges can be trimmed in early summer and autumn. Some fast-growing hedges such as privet and leylandii may need trimming three times a year, in late spring, early summer and autumn. Late summer is a good time to trim deciduous hedges such as beech in hornbeam – when they are still leaf but growth has slowed down. Native hedges such as hawthorn, hazel and blackthorn should be trimmed in autumn or winter.

What is the law on trimming hedges?

Nesting season is usually between February and early August, but always check hedges in late August and September in case of any late nesting birds. Under the Wildlife and Countryside Act 1981, it is illegal to disturb any nesting bird or destroy any nest while it is in use or being built.