Why Is My Box Hedge Going Brown or Bare?

By Paul Watmore, Director at Grasslands Nursery

A browning or bare box hedge usually means one of three things: box blight (brown patches with black streaks on the stems), box tree caterpillar (webbing and stripped leaves), or harmless winter bronzing. Telling them apart decides what to do.

Box blight

Box blight is a fungal disease. Look for brown or bare patches, rapid leaf loss, and tell-tale dark brown or black streaks on the stems. It spreads fastest in warm, wet, humid weather. Cut out affected growth, improve airflow, clear all debris, and disinfect tools — badly affected hedges are often best replaced.

Box tree caterpillar

If you see fine webbing and green-and-black caterpillars stripping the leaves, it is box tree caterpillar, not blight. Pick them off, use pheromone traps to monitor, and treat promptly if numbers build.

Winter bronzing (usually harmless)

An orange or bronze cast over the whole hedge in cold, exposed conditions over winter is usually just winter bronzing — a stress response that greens up again in spring. A spring feed and some shelter help, and it does no lasting harm.

Drought and waterlogging

Browning can also be simple drought (crispy leaves, dry soil) or waterlogging (yellowing, wet soil). Check the soil and correct the watering.

Can box recover, and what else can you plant?

Winter bronzing and mild caterpillar damage recover well. Blight is harder — mild cases can be managed, but badly hit hedges are best replaced with Ilex crenata or another box alternative. See also our guide to box hedge care and preventing blight, and browse our box hedging.

FAQs

Why is my box hedge going brown?
The three main causes are box blight (brown patches, black stem streaks), box tree caterpillar (webbing, stripped leaves) and harmless winter bronzing. Drought or waterlogging can also brown it.

Is it box blight or caterpillar?
Blight shows brown patches and black streaks on the stems; caterpillar shows fine webbing and green caterpillars eating the leaves. Check the stems and look for webbing.

What is winter bronzing?
An orange-bronze cast over the whole hedge in cold, exposed winters — a harmless stress response that greens up again in spring.

Can a box hedge recover?
Winter bronzing and mild caterpillar damage recover well; blight is harder — mild cases can be managed but badly affected hedges are best replaced, ideally with a blight-resistant alternative.

About the author: Paul Watmore is a director at Grasslands Nursery, a family-run plant nursery near Knutsford, Cheshire, growing hedging, pleached trees and specimen plants since 1984. Meet the team →