Tips for pruning evergreen hedges

When to prune

The best time to prune evergreen hedges to keep them looking neat is between June and September.

How often to prune

Most evergreen hedges need pruning twice during the season. Vigorous plants, such as privet and conifers, can be pruned up to four times a year while slower growers like holly need pruning just once, in late summer.

Pruning shape

The base of a hedge needs to be wider than the top. This restricts the dominant top growth, which would otherwise shade out the bottom and cause it to become bare.

Tips for box

To avoid box blight – a fungal disease that can kill box plants – never trim box in wet weather or any later than August, when the spores are more prevalent. While you are pruning, look out for damage caused by the box tree caterpillar, which can ruin plants. Examine the plant carefully for the green and black caterpillars and their tell-tale droppings, webbing and dieback. Take action promptly.

Tips for conifers

Take care to only trim conifers lightly, never cutting back into old, leafless stems - they can't produce fresh foliage, so you'll end up with bare patches. Yew is an exception. Most conifers produce vigorous upright growth; for young hedges, trim out the tops to encourage side branches low down. Never trim later than August so plants can recover before winter arrives. You can use the trimmings as cuttings.

Tips for large-leaved hedges

Prune large-leaved hedges such as laurel, holly, griselinia (pictured) and elaeagnus during July and August, as by then they'll have started to look unruly. A trim once a year should creating a good finish.

Tips for privet

Privet grows fast and will grow very large if left to its own devices. To keep it in check, trim several times between May and September.