Bedding plants

Thuja turns brown - Miniermoth is to blame

Thuja turns brown - Miniermoth is to blame

We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

If the tips of the thuja suddenly turn brown, one thing is mostly to blame: the leaf miner. If you don't intervene and do something here, you have to worry about your thujen.

The Miner Moth is to blame

If you let your gaze wander through the neighboring gardens, you will surely notice one thing: Thujen can be found everywhere. And that's not even surprising, because thujen are perfect hedge plants. Strung together, they can grow into a stately hedge in just a few years. So they offer quick and opaque privacy protection, which is also easy to care for and inexpensive. So it doesn't matter if a plant dies.

It is bad, however, when all of the trees of life, as the Thujen are also called, get brown tips and look sickly. Then at the latest it is time that you take a closer look at the plants. If the tips turn brown over time, then this is a clear sign that something is wrong here.

Usually several thujen are affected

Too often it happens that Thujen suddenly turn brown and die in a very short time. Of course, this is particularly annoying within a hedge. And it is not just there that one plant is affected, often several are affected. One culprit is usually responsible for the death of the plants: the leaf miner. To be precise, it is the Thuja leaf miner.

Damage symptoms:

The Thuja leaf miner is a small butterfly that belongs to the family of spider moths. And it is precisely this that lays its eggs on the leaf scales in June / July. The caterpillars hatching from it then eat their way through the tips of the shoots and actually hollow them out. The result: the infected branches of the Thujen initially turn yellow from the top and then brown to gray over time.

In the meantime, the caterpillars that overwinter in the shoots pupate. The new generation of moths hatches in June / July. Just like the previous generation, they lay eggs on the scaly shoots of the thuja again. So the whole game starts all over again.

Control measures:


If you notice an infestation with the leaf miner, then quick action is important to save your life trees. In the case of a mild infestation, it is advisable to cut the shoot tips in spring and thus before the moths hatch. This is how you can control the spread of the pest.

In the case of a heavy infestation, however, you have to do a lot more. A drastic pruning of the shoots is even necessary here. But don't worry, your Thujen will then sprout again splendidly.


Do not dispose of the infected branches in the compost, but in the household waste. You can also burn the clippings. This will prevent the pests from spreading.


It is also advisable to spray an insecticide against the leaf moths. This agent is then intended on the one hand to prevent egg laying and on the other hand to prevent the newly hatched caterpillars from entering the shoots. Therefore it is always advisable to spray twice. Once in early June to meet the moths and once when the caterpillars have hatched. Recommended insecticides to control the leaf miner are e.g. COMPO Triathlon Universal Insect-free AF ​​(e.g. available here) with the active ingredients from nature or Bayer pest-free Calypso Perfect AF (available here e.g.), which is not dangerous to bees.

If you prefer to rely on natural pesticides, you can spray your thujen regularly with nettle soy. To do this, fill 1 kg of nettles and 10 liters of water in a vat, close them and leave them in the sun for 14 days. Stirring regularly is important. You can then use the liquid manure directly.


  1. Burhbank

    I accept it with pleasure. In my opinion, this is relevant, I will take part in the discussion. I know that together we can come to the right answer.

  2. Zulkizilkree

    Bravo, your phrase will come in handy

  3. Augustine

    Bravo, brilliant idea

  4. Khan

    Looks like Lenya in nature.

  5. Gilchrist

    the remarkable thought

Write a message