Garden Q&A: What's eating my viburnum, and what can I do about it?

Whether you're a gardening beginner or expert, Irish Examiner columnist Peter Dowdall has the answer to your questions  

The pink and white Viburnum tinus laurustinus 'Lisa Rose' in flower. File picture

Question

My Viburnum tinus is being eaten and is very badly damaged. What's causing it, and what can I do? It's an old plant.

Answer

From the photograph you sent with your email, it looks very much like vine weevil damage, though it is not possible to say with absolute certainty from the foliage alone. 

The irregular notching and heavy chewing along the leaf edges are typical of adult vine weevils feeding at night. While this level of leaf damage looks alarming, it is usually only cosmetic. 

The greater concern is below ground, where the larvae may be feeding on the roots and weakening the plant over time. 

It is worth checking the soil around the base for small, cream-coloured, C-shaped grubs. If present, treatment with a biological control, such as nematodes, is the most effective approach. 

Supporting the plant with good soil care, including the use of a biochar-based feed, will help it recover and maintain strength.

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