First appearing in Germany in 2007, the box tree moth now has many regions of Germany, Austria and Switzerland under its control. Fighting the pest is lengthy and complicated, so many gardeners desperately resort to poison injection. However, this often causes even more damage.
What options are there for spraying a boxwood?
To protect a boxwood from pests, you can use environmentally friendly sprays such as Bacillus thuringiensis (B.t.) or nematodes of the type Steinernema carpocapsae. Avoid chemical sprays as they are harmful to bees, bumblebees and songbirds.
Avoid chemical sprays if possible
Chemical sprays not only work against the box tree borer and other pests, but also against beneficial insects. They are one of the main causes of the massive death of bees, bumblebees and butterflies - and this even applies to the products on which you can read the label “Bee-friendly”. Chemical pesticides not only destroy insects, but also have a damaging effect on songbirds and other garden inhabitants. They represent a serious intervention in the natural cycle and should therefore only be used after careful consideration of all the 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 (€7.00 on Amazon) (B.t.) used, which is also approved for the home garden. The borer caterpillars ingest the bacteria when they eat the boxwood and die quickly. In order for the treatment to be successful, you should carry it out by the end of April at the latest. You proceed as follows:
- Only spray when the sky is overcast, never when the sun is shining.
- Bacillus thuringiensis (B.t.) is very sensitive to UV light.
- Optimally, the temperatures on the day of treatment are at least 18 degrees Celsius.
- Then the caterpillars are active and take in a particularly large number of bacteria.
- The affected 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 product more often or in a higher concentration than specified - a lot doesn't always help in this case! In addition to Bacillus thuringiensis, nematodes of the type Steinernema carpocapsae can also be used as sprays. However, these only work if the box has not been previously treated with chemical pesticides!
Tip
The best way to get rid of the boxwood moth is mechanical in 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 by generating heat.
