First appearing in Germany in 2007, the box tree moth now has many regions of Germany, Austria and Switzerland under control. Combating the pest is lengthy and complicated, so many gardeners desperately resort to lethal injections. However, this often causes even more damage.
In the case of a very severe infestation of the box tree moth, spraying is often the only thing that helps
Avoid chemical sprays as much as possible
Chemical sprays are not only effective against the box tree moth and other pests, but also against beneficial insects. They are one of the main causes of the massive deaths of bees, bumblebees and butterflies - and that applies to even the media that you can read "bee friendly" on. Chemical pesticides not only destroy insects, but also have a damaging effect on songbirds and other garden dwellers. They represent a serious intervention in the natural cycle and should therefore only be used after careful consideration of all advantages and disadvantages.
Environmentally friendly sprays
However, there are more environmentally friendly alternatives that have a less drastic impact on nature and the garden. The bacterium Bacillus thuringiensis (B.t.), which is also approved for home gardens, has been used in organic farming for a long time. The borer caterpillars absorb the bacteria when they eat the boxwood and die off quickly. In order for the treatment to be successful, you should carry it out no later than the end of April. You do this as follows:
- Only spray when the sky is overcast, never in bright sunshine.
- Bacillus thuringiensis (B.t.) is very sensitive to UV light.
- Ideally, the temperatures on the day of treatment should be at least 18 degrees Celsius.
- Then the caterpillars are active and pick up a particularly large number of bacteria.
- The infested boxwood must be sprayed dripping wet inside and out.
When using it, be sure to follow the information and instructions given on the package. Do not use the remedy more often or in a higher concentration than specified - in this case, a lot doesn't always help much! In addition to Bacillus thuringiensis, nematodes of the Steinernema carpocapsae species can also be used as sprays. However, these only work if the box has not been treated with chemical pesticides beforehand!
tips
The best way to get the box tree moth under control is anyway of a mechanical nature: remove the caterpillars with the help of a high-pressure cleaner or a vacuum cleaner. You can also put an opaque garbage bag over the box and kill the caterpillars with the heat generated.