Box tree moth threat: Safeguard your garden’s elegance
Boxwood is a highlight of many gardens—elegant, evergreen, and easy to shape. However, for several years, its biggest adversary has been the box tree moth. This inconspicuous pest can completely devastate even mature, multi-year plants in a short period. How can you recognize and effectively combat it?
Box Tree Moth (Cydalima perspectalis) is an invasive moth species originating from Asia. Over the past few years, it has spread across most of Europe. It appeared in Poland relatively recently but quickly began destroying boxwoods in gardens.
The main culprits are the moth larvae. They have a light green colour with dark stripes and can reach a length of up to 4 centimetres. They feed intensively on the leaves and young shoots of boxwood, which significantly weakens the plant and, in extreme cases, can lead to its complete demise. Infested shrubs quickly lose their leaves, begin to dry out, and noticeably decline in appearance.
Signs of box tree moth feeding
The first concerning symptom that may indicate the presence of the box tree moth is fine webs and black lumps of feces on the plant's leaves. Over time, more significant damages appear. The leaves turn yellow, become shredded, and then entire sections of the bush begin to die.
It's worth regularly inspecting the inside of the plants, as the larvae often start feeding from the centre of the bush. Hidden deep within the thicket of branches, they remain invisible in the early phase of the attack, making a quick response challenging.
Dr. Engineer Mateusz Sowelo, curator of the collection at the Botanical Garden of Adam Mickiewicz University in Poznań, emphasized in an interview with tvnmeteo.pl that the appearance of this insect on boxwood can result in the complete destruction of the plant within just a few days.
"Currently, there are no natural predators in Poland, such as other insects or birds that eat the larvae of this moth. The box tree moth mercilessly devours boxwoods. If we see many of them on our boxwood on Thursday or Friday, by Monday, defoliation will have occurred—only the branches will remain, with all the leaves eaten," he emphasized.
Effective methods for combating the box tree moth
The most crucial element in the fight against the box tree moth is taking action as soon as the first signs of its presence are noticed. One of the most recommended methods is using biological preparations containing "Bacillus thuringiensis" bacteria. These agents are safe for both humans and animals and very effective in eliminating insects.
Sprays should be applied at regular intervals, especially in spring and summer, when the moth goes through various developmental stages. In cases of severe infestation, it is also advisable to mechanically remove larvae from the plants and prune infested shoots.
Take care of plants before a problem arises
The box tree moth thrives best in dense, moist, and poorly ventilated shrubs, so prevention is crucial. Pruning boxwood to maintain its airflow is worthwhile. This reduces the attractiveness of the shrub for female moths seeking a place to lay eggs.
Regularly removing dry leaves and organic debris from under the plants also decreases the risk of pest development. Applying pheromone traps is also a good solution. These can help monitor the presence of adult moths and allow for quick action before larvae appear.
