Lily Beetle
Pest · Commonly affects: Lilies, Asiatic lilies, Oriental lilies, Tiger lilies, Martagon lilies, Fritillaries
Lily beetle is a conspicuous and damaging pest of true lilies and fritillaries in UK gardens. Both adults and grubs feed on leaves, often appearing from spring onwards. Its bright colour makes adults easy to recognise, but the grubs are well camouflaged, so regular inspections are needed to protect flowering stems.
How to identify it
Adults are bright scarlet red beetles, about 6 to 8 mm long, with black legs, head and underside. When disturbed they may drop to the soil and land upside down, showing their dark underside. Eggs are orange-red and laid in lines beneath leaves. The reddish, orange or brown grubs grow to about 10 mm and conceal themselves under a sticky coating of their own black excrement. Look for chewed leaves and black smears.
Damage
Adults and grubs make holes in lily leaves, but a severe infestation can strip foliage and buds almost completely. Defoliated plants lose strength, produce fewer flowers and may make smaller bulbs for the following season. Fritillaries can be damaged in the same way. The effect is most severe on young plants and in repeated attacks over several years.
Prevention
Inspect lilies and fritillaries every few days from early spring, including the undersides of leaves where eggs are laid. Check newly bought bulbs and potted plants before placing them among established specimens. Keep the area around emerging shoots free of old plant debris, which makes inspection easier. Grow plants strongly with suitable watering and spacing. Encourage birds and predatory insects in the wider garden, although direct checking remains the most reliable preventative measure.
How to manage it
Hand-pick adult beetles, eggs and grubs regularly, carrying a small container beneath the stem because adults often drop when disturbed. Wipe or remove grub-infested leaves where practical, taking care with their black coating. Repeat checks at least weekly through the growing season, and more often when new growth is soft. Remove heavily damaged foliage after flowering only if enough healthy leaf remains to support the bulb. Dispose of collected pests in household waste.
Lily Beetle: frequently asked questions
How do I identify lily beetle?
Adults are bright scarlet red beetles, about 6 to 8 mm long, with black legs, head and underside.
How do I prevent lily beetle?
Inspect lilies and fritillaries every few days from early spring, including the undersides of leaves where eggs are laid.
How do I get rid of lily beetle?
Hand-pick adult beetles, eggs and grubs regularly, carrying a small container beneath the stem because adults often drop when disturbed.
General guidance for UK home gardens and allotments, focused on prevention and non-chemical control. For a confirmed diagnosis, the RHS or a local garden centre can help. Page updated 19 Sep 2026.