When should you trim and prune your hedges?

Hedges, not unlike other plants also require their fair share of maintenance in order to look lush and healthy. They need formative pruning and general maintenance trimming to stay within bounds. As hedges are often made out of different varieties of trees and shrubs, it’s only normal that their pruning times vary. Same as with trees, there’s also a “best time” to cut your hedges back as well.

When to prune your hedges to stimulate growth

gardener trimming hedge

Formative pruning is performed for the first two to three years after the hedge has been planted. It’s usually carried out either in winter or early spring. While regular yearly pruning depends on the type of hedge you have.

The intention behind pruning hedges is to prevent dead or dying branches from harming neighbouring plants and people. By removing these branches you allow the hedge’s flowers or fruits to blossom. Unlike maintenance trimming, pruning isn’t done to slow down the growth of the hedge, but to actually stimulate it. Other reasons gardeners prune their hedges is to remove diseased or pest-ridden branches.

The best time to perform maintenance hedge trimming

gardener trimming top of a hedge

Maintenance trimming refers to tidying up a hedge or shrub by cutting back on overgrown branches. While pruning focuses on the hedge’s health and the safety of its surroundings, trimming is done mainly for aesthetic purposes. Yet, excessive overgrowth can also be harmful to your hedge as it can reduce the amount of light and moisture it receives, stuttering its growth. Therefore trimming is just as important as pruning.

Maintenance trimming is usually carried out once a year for informal hedges and twice for formal ones. However, there are certain hedges which might require three cuts a year. If you’re wondering when to trim your hedges, it’s usually done sometime between spring and summer.

You do, however, have to take into account potential nesting birds as nesting season may run from March to August. If you notice any nesting activity in your hedges, consider postponing the maintenance trimming for after the season passes.

When it comes to pruning and trimming, hedges fall into three categories.

Upright plants

Privet Hedges
Privet Hedges

Maintenance trimming of young privet hedges is carried out between early spring and late summer. By trimming back your privet hedge, six to eight inches from the ground when new growth starts will encourage branching at the base of the plant. This will promote root growth and aid newer shrubs in establishing themselves in the garden. From there on, for every new foot of growth, trim back six inches. Cease trimming in late summer as not to encourage fall growth, which can lead to winter damage.

When should you prune a privet hedge? Privet hedge pruning is performed in late winter. This includes removing dead or damaged branches and opening the interior of the hedge. All of this should be done before spring growth starts.

Hawthorn Hedges
Hawthorn Hedges

If you’re wondering when to cut your hawthorn hedge, do it once in May after flowering and a second time in autumn when the sides start looking a bit ragged. Remember to keep the tops of the hedge levelled and its bottom wider (to let light get to the lower branches).

Pruning of hawthorn hedges is best performed when the shrub is dormant, i.e during the winter season. The reason you would want to prune your hedge during winter is to encourage a stronger blossom the following spring.

Buxus Hedges
Buxus Hedges

Trim your Buxus plant at least 2 times a year. First in June when parts become woody and a second time between August and September. Perform cutting only on cloudy days, however, if this isn’t an option, regularly spray the seedlings to prevent leaves from branching.

As to when you should prune your Buxus plant in order to get rid of dead and sick branches, the answer is simple, do it in spring. Train smaller branches so that they take the right shape and prune large branches to prevent them from growing outwards.

Escallonia Hedges
Escallonia Hedges

Trimming of Escallonia is performed in May and late August if you’re looking after a formal hedge without flowers.

Escallonia pruning is carried out at the end of winter for rebalancing the shape of the hedge and again at the end of summer, after the bloom period.

Stocky deciduous plants

Beech Hedges
Beech Hedges

Beech hedge trimming is carried out in early June to keep the hedge bushy. And again in early august to help produce a flush of new leaves. These will decorate the hedge throughout winter.

When can you prune a beech hedge? Pruning of beech hedges isn’t really necessary, however, if there’re any odd branches you’d like to prune, do it in the winter when the tree is dormant.

Hazel Hedge
Hazel Hedge

Trimming of hazel hedges is performed between late winter and mid-spring(between February and April). This must be done before the new leaves begin to appear on the hedges stems, mostly for aesthetic reasons.

Prune diseased or damaged stems the moment you notice them, to keep the hedge healthy and safe. Also, if you notice any suckers stemming from your hedge, be sure to act ASAP. Prune the sucker a quarter of an inch above its base as to not harm your hedge.

Forsythia Hedge
Forsythia Hedge

Trim Forsythia hedges lightly in late July or August. Use hedge clippers or shears to just shape the hedge without doing any serious cutting.

The prime time for pruning Forsythia is in spring between the time current blossoms die and new buds set. During that time cut back all shoots which flowered by at least a third, making the cut at a parallel shoot.

Hornbeam Hedge
Hornbeam Hedge

Trimming of hornbeam hedges is done twice a year for a denser hedge. Once at the beginning of June and again at the start of September.

Rejuvenation pruning is done in stages over a period of three years. Perform it in winter by cutting a third of the branches down to around 15 inches from the ground. Repeat this each year. Avoid pruning only the outermost branches of your hedge. Select branches from all over the shrub.

Conifers and most evergreens

Laurel Hedges
Laurel Hedges

To encourage laurel growth, trim the hedge in July or August. But bare in mind that this hedge has large, tough leaves and is best trimmed using secateurs.

Pruning of Laurel hedges can be performed at any time up until the end of summer. However, it’s best done in spring. Late pruning should be avoided as it can subject the hedge to winter damage.

Leyland cypress
Leyland cypress

Leylandii should be trimmed up to three times a year. Once in April, July and late August. Although it’s quite the fast-growing hedge, avoid cutting beyond its green growth as it might not recover. Therefore when dealing with Leylandii, go over it often, but only little by little to help keep it under control.

The best time of year to prune your Leylandii hedge is in late spring as this gives it a chance to recover and regrow a bit before winter.

Lawson cypress
Lawson cypress

Trim your lawson cypress hedge towards the end of the year, between September and December. Trim it any earlier and the poor conifer might bleed

Prune dead branches between March and October to keep your hedge lively and healthy.

Pyracantha
Pyracantha

The pyracantha hedge is a very tough plant which can be trimmed at almost any time. However, ideally, it’s best to trim it lightly to your desired shape in spring and again in late summer.

Prune your pyracantha hedge in late spring and wait for an abundance of new flower branches to pop up the following year.

Informal/flowering hedges

For informal hedges, prune the area in which flowers are desired, once at the right time of year. This will encourage flowering the following year. If you prune your hedge at the wrong time, you might remove the growth that is supposed to flower the following year.

Plants that flower on the current season’s growth need to be pruned only once in spring. That alone will be enough for flowers to bloom later the same year.

For plants that flower on one-year-old growth, prune the current season’s growth by half in summer.

As for berry producing shrubs, delay the pruning until the berries go away.