How to guide on spotting and ridding lily beetles.
Often mistaken for ladybirds, lily beetles are tiny pests that can munch through the flowers and seedpods of lilies and other members of the lily family.
Identifying
Between September and April, lily beetles lay eggs on the undersides of leaves. After about a week, the eggs hatch into reddish-brown, maggot-like grubs. These larvae cover themselves in their own wet, black excrement and it is believed to deter predators or serve as camouflage. They grow to about 6–8mm in length and have black heads.
Treatment
Pick off the grubs and adults as soon as possible. Adult beetles will drop to the ground at the slightest touch, so place newspaper beneath the plants to catch them. Be quick—and crush them!
Deter
Companion plant lilies with species that naturally repel beetles, such as alliums, marigolds, and certain herbs.
Rotate the location of your lilies each year to disrupt the beetles’ life cycle and make it harder for them to find host plants.
Encourage natural predators such as birds and beneficial insects to feed on the beetles.
Have You Seen a Lily Beetle? The RHS Wants to Know
As part of ongoing research, the RHS is collecting sightings of lily beetles. If you’ve spotted one, submit your record via their official survey (estimated time: 2 minutes).