PestChewing insects
Lily beetle
Bright red beetles and their dung-covered larvae that strip the leaves and flowers of lilies and fritillaries.
Also known as: Scarlet lily beetle, Lilioceris lilii
Symptoms and identification
Holes in leaves and petals, with bright red beetles and slimy, brownish larvae covered in their own excrement on leaf undersides. Plants can be stripped bare.
Causes
The beetles overwinter in soil and emerge in spring. They are widespread in the UK and the north-eastern US and Canada.
Organic treatment
Hand-pick adults, larvae and orange egg clusters under leaves. Neem oil can deter larvae.
Prevention
Check lilies daily from spring; beetles drop to the ground when disturbed, so hold a hand underneath.
Chemical treatment (use with care)
Use an insecticide labelled for lily beetle, avoiding open flowers visited by bees.