Lily Leaf Beetle

Lily leaf beetles prefer lilies over everything else, but you may find them damaging your potatoes and hollyhocks, as well.

Scarlet lily beetle (Bj.schoenmakers) Public Domain

Scarlet lily leaf beetle (Lilioceris lilii) earns its name by devouring lilies of every shape and size. Native to Europe, this pest made its way to Canada in 1945 and reached the U.S. in 1992. While they may not yet be in your neighborhood, they might. So it’s a good idea to know what they look like and how to control them - just in case.

Lily leaf beetle description

The bright reddish-orange wing cover of lily leaf beetles makes them easy to spot. Black legs, head, and antennae stand out in clear contrast against green leaves. Adults average 1/2” long.

Eggs are irregularly shaped and laid in rows. At first they are tan colored. Just before they hatch, they turn bright red. Larvae look like tiny brown, orange, yellow, or even greenish slugs with black heads.

Lily leaf beetle lifecycle

Eggs are laid on host plants, usually on the underside of leaves. After hatching, larvae feed for 2 - 3 weeks before dropping to the ground to pupate in the soil. Adults overwinter in sheltered areas that may not necessarily be near host plants. In spring, they emerge and mate. Each female might lay 250-450 eggs.

Damage caused by lily leaf beetles

Both adults and larvae feed on buds and leaves. Very often, nothing is left but stems. Lily leaf beetle larvae have a nasty habit of collecting their own excrement on their backs. This is believed to be a defense mechanism. I’ll bet it works, too!

Lily leaf beetle control

Hand-picking is the best control method. Severe infestations may warrant neem oil or spinosad application.