Insects that are your lilies’ worst nightmare
Red lily beetles – both adults and larvae – can defoliate lilies and fritillaries in a day, and I really mean strip them back to a stick. If you think it’s a ladybird without spots, it isn’t, I’m afraid. Should you be in any doubt, adults are 8mm long, bright red with a black head, underside and legs and very long antennae. Eggs of red lily beetles are 1mm long and orange-red, found in groups on the underside of leaves.
Wherever you live, you probably know them by a different name – scarlet lily beetle, lily leaf beetle or simply the lily beetle. Whatever you know it as, Lilioceris lilii eats the leaves, stems, buds, and flowers of members of the lily family. Its absolute favourites for egg-laying purposes are lilies and fritillaries (crown imperials).
Asiatic lilies are the most susceptible to attack, followed by fritillaries, but Oriental lilies show a bit of resistance. Fortunately, daylilies (Hemerocallis) aren’t attacked by red lily beetles. Read more about lilies.
Larvae are absolutely despicable, with orange bodies and black heads, but are normally covered with their own slimy black poo. The fully grown larvae are 8-10mm long. The pupal stage is in the soil. If adults are unable to escape an attacker, they will ‘squeak’ by rubbing two parts of their body together to try and shock the predator.
The beetle became established in Surrey in 1939 and stayed in SE England until the late 1980s. It has now spread to the NE of Scotland and is an annual nuisance in my garden. If you spot them, report them to www.rhs.org.uk.
Organic red lily beetle controls
- Bantams like to eat the adults, but not the disgusting larvae.
- Grow lilies in pots and change the soil every winter – then spread it out thinly and let the birds exact your revenge. Thanks to Harriet Rycroft for that one.
- Carefully dig in the top half-inch of the soil, as they hide just under the surface. Be ready to get them when they pop out.
- The adults are jittery when you try to pick them up by hand and drop them onto the soil upside down. As they have black bellies, you can’t see them, so put a light-coloured cloth under the plant before you hand-pick to see them.
- There’s a suggestion that the Chelone (Turtlehead) planted next to lilies may act as a repellent.
- Try the G3 red lily beetle organic control spray by Grazers.
