Garden calendar

Protect box trees properly!

Protect your plants now! Recognize and fight box tree moths in good time — in a few steps:
1. From April, check the box tree for spun-in cocoons with pupae of the box tree moth and damage caused by feeding.
2. If there is a small infestation, collect the caterpillars of the box tree moth.
3. You can remove caterpillars and pupae by spraying the boxwood with a strong jet of water.
4. Set up box tree moth traps to reduce infestation and schedule spraying. The traps are mainly used for monitoring in the garden. The trap is not a method of fighting, but a means of control.
5.Fight naturally with caterpillar spray (Bacillus thuringiensis subspec). The agent is ideal for biological control and works effectively.

Things to know about the pest

Box tree moths are pests that attack box trees in the garden or on the balcony and can quickly and completely destroy them. The corn moth lays its eggs primarily on the outer leaves of boxwood plants. Larvae and eventually caterpillars develop from the eggs.

The box tree moth caterpillars are easy to recognize. When fully grown, they are 5 cm long and green with black dots. In good conditions, the pest spreads quickly in the garden and severely damages the trees. Box tree moths are not native and have therefore not yet had any natural enemies. First, the caterpillars eat the leaves to the point of defecating and finally even the bark. If left untreated, the boxwood suffers so badly that the plant can quickly die off . Affected plants are covered with webs and the leaves are eaten down to the midribs. There is no danger to most other plants in the garden. become partialSpindle shrubs (Euonymus alatus and Euonymus japonicus) and Japanese holly (Ilex purpurea) infest. Tip: As a preventive measure, you can spray regularly with Bio Plant Treatment . This biological preparation strengthens the plant’s own immune system and makes the boxwood more resistant to boxwood moths. Weekly use is important.

Lifestyle of the box tree moth

The Box Tree Moth

The moth, which originates from East Asia, has been known in Germany since 2006. It is fairly inconspicuous, white with a slight black or tan border on the wings and has a wingspan of 40 to 45mm. The moth sits mainly under the leaves and lives only about 10 days. During this time, the female moths lay their eggs. In climatically favorable regions there can be up to three box tree moth generations. Due to the mild winter, caterpillars can hibernate and start feeding from the middle to the end of April , from the end of May the voracious caterpillars curl up and after the pupal dormancy from June they can be recognized as butterflies.

Control of the box tree moth

We don’t want you to recognize any damage too late and your plants to be irreparably damaged. The green caterpillars cause great damage within a very short time, this must be avoided, recognized in good time and combated.

With our tips you can protect your valuable plants without using chemicals:

  • The right time for the first check is in early spring. Look inside the plant to see if there are webs from last year. The borer spends the winter spun in cocoons inside the boxwood. The pests become active at constant temperatures above 8 °C. An infestation can become a problem within a few days , as the insect is very voracious and can quickly become bare.
  • When the first infestation occurs, you can read off the webs and the borer caterpillars by hand.
  • In the case of large-scale infestation, the boxwood can be hosed down with a hard jet of water and the pests that have fallen down can be collected .
  • In the case of severe infestation, treatment with caterpillar spray (Bacillus thuringiensis subspec), a biological agent, is essential to preserve the valuable trees . Make sure you use the biological spray thoroughly, because the insects are often inside the boxwood. Repeat spraying is urgently needed as some larvae have not yet emerged from their cocoons and re-infestation by caterpillars may occur. Beneficial insects are not affected by the use of the biological insecticide.

Box trees that are already infested are cut into shape with hedge trimmers . This allows you to eliminate the different stages of the box tree moth (caterpillars and pupae). It is important that you dispose of the clippings with household waste and do not compost them.

Early detection of pest infestation is crucial for successful control. You should therefore check the box plants regularly once a week from the end of March .

Interesting facts about box tree moth traps

  • The sex scent (pheromone) contained in the traps attracts male moths . They are therefore not involved in a pairing.
  • The pheromone is long-lasting and lasts for the entire season.
  • The traps are used to determine infestation and, in the case of severe infestation, to determine the treatment date.
  • Place the traps close to the box trees.

Of course we hope that your plants are not affected. If it does, we wish you and your boxwood every success in the fight against the caterpillars — with the right treatment, your boxwood can hopefully be saved!


The boxwood – privacy screen and topiary for your garden
The boxwood can be used as a hedge or as an ornamental shrub with topiary. Find out everything about planting and care here.