Skip to content

The red lily leaf beetle: a devastating creature

For those of us who love to grow lilies there is a huge threat for all of us. The red lily leaf beetle or scarlet lily leaf beetle ( Liliocerislilii ) is an invasive beetle that may be in your garden.
red lily leaf beetle
An infestation of the red lily leaf beetle can decimate a lily bed in a short time. Photo by Patricia Hanbidge

 

For those of us who love to grow lilies there is a huge threat for all of us. The red lily leaf beetle or scarlet lily leaf beetle (Liliocerislilii) is an invasive beetle that may be in your garden. It was introduced into Canada in the 1940s and has quickly spread throughout Canada and the United States.

It feeds on any type of lily including Asiatic, martagon, oriental, tiger and trumpet lilies as well as fritillaries. It does not feed on daylilies, which are actually not a true lily. If you have this beetle in your garden it will become evident quickly as they can devastate your lily bed, seemingly overnight. They will eat every part of the plant: leaves, stems, buds and even the flowers.

They will feed, mate and produce more of these demons quickly. The adults are six to eight millimetres long with a rectangular body that is bright red. The underside, head, antennae and legs are black. The adults will overwinter in the soil or in leaf litter and will emerge with the first warm days of spring. They begin to feed and will mate and lay eggs on any available lilies. The eggs are laid on the underside of the leaves in groups of three to 12 and are generally orange. When the larvae hatch, the devastation becomes even greater. This stage of life is rather disgusting as the slimy larvae will cover themselves in their own excrement in the hope of distracting predators. They are slimy enough without this addition and the damage they do is appalling. Once the larvae go through four stages or instars they will leave the plant and form a cocoon by gluing soil particles together. New adults will emerge by mid-summer only to continue their devastating cycle.

So, lilies beware, as these little critters can devastate your entire lily garden in a short period of time If you catch them early, then they are easy to handpick and squish, but you need to be quick as they are a bit wily and if they drop onto their backs their black bellies are hard to see. It might help to lay a piece of white paper under the lilies when hunting the adult beetles. If you miss even one, you will see the devastation continue, so beware and watch your lilies closely. I made the mistake of being absent for a couple of weeks and came back to a huge mess. My diligence is now unequalled, as dealing with the larvae is way worse than dealing with these little red beetles in their adult form.

Hanbidge is the Lead Horticulturist with Orchid Horticulture. Find us at www.orchidhort.com; by phone at 306-931-4769; by email at info@orchidhort.com; on facebook @orchidhort and on instagram at #orchidhort.