The right fight at the right time will make you successful in the fight against the box tree moth. Find out here what works and when.
The best fighting method is of no use to your boxwood (Buxus) if the wrong time is chosen. Because in many phases of its life the box tree moth (Cydalima perspectalis) is immune to attackers thanks to sophisticated tactics. So that you always have a suitable action strategy ready, we have selected the right times for each approach.
If you want to effectively control the box tree moth, you need to delve deep into its biology and development cycle - or read our guide to find out when the best methods to control the box tree moth are traps, cutting, water, harvesting, or spraying.
When to set box tree moth traps?
The short-lived moths of the box tree moth are mainly active at night, when they mate and lay eggs. From these, voracious larvae will hatch soon after the flight of the moth. Therefore, observing the flight of the moth is an important first step if you want to fight the moth moth successfully from the start. With the help of pheromone traps for box tree moths, such as the Plantura moth trap, you will know when eggs and caterpillars are to be expected. Traps should be used in June, August and September.
Note: In very warm years, the development of the moths can accelerate, so that the moth flight takes place two to four weeks earlier.
When to collect box tree moths?
Collecting or cutting out entire shoots with box tree moth caterpillars is only worthwhile if the infestation is low. Checking for webs in the inner and outer areas of box trees can take place from mid-April. Because the development time of the moth shifts depending on the weather, we recommend at least monthly checks until September.
In the best case, it should be collected when the early larvae stages are still spun into webs and leaves inside theshrub life - at this point the infestation is not yet visible from the outside. If the caterpillars later eat freely in the outer areas, they can also be rinsed off with a hard jet of water. Incidentally, you don't have to worry about skin contact with the green caterpillars: the box tree moth is only poisonous internally. You can find more on this topic in our special article “Are box tree moths poisonous?”. For this reason, the disposal of the box tree moth is not as complicated as one might think.
Tip: If you spot very young larvae and eggs of the box tree moth on the outside of your box tree about 2 weeks after the moth has taken flight, immediate pruning is a good method of removing the pests.
When to spray against the box tree moth?
Eggs and pupae are protected against sprays, moths fly away and young larvae stay in webs and leaf coverings. If an infestation is to be treated with sprays, the caterpillars should remain free-feeding in the outer areas of the shrub so that they can be hit by the spray. This is usually the case in the second half of April and early July. Of course, there are also systemic agents that are ingested by the caterpillars by feeding on the boxwood. In order to reduce the use of chemical pesticides, however, the use of so-called Bt preparations is recommended, such as our Plantura Zünslerfrei XenTari®. If these hit the caterpillar directly, the control success is very high.
Summary: When to Fight the Boxwood Moth?
- Pheromone traps should be used in June, August and September. In warm years the moths of the moth can appear earlier.
- It makes sense to check for webs, droppings and borer caterpillars at least once a month between April and September.
- Two weeks after moth flight, eggs and young larvae can be removed by cutting.
- The best time to spray against the box tree moth is in the second half of April and the beginning of July.
We have summarized options for combating the borer in our special article for you.