What’s black and slimy and eating my Lilies?! No it’s not a joke!
If your lilies or fritillaries are being merrily munched as soon as your back is turned, the most likely culprit is the lily beetle or their larvae.
The lily beetle is a red beetle which munches both petals and leaves. It can decimate your lilies and cause poor bulb development that can affect next year’s flowers.
The lily beetle larvae are small grubs which appear slimy and black. This is due to the grubs being covered in their own excrement (nice!) to make them unappealing to predators. These little critters feed on the underside of the leaves, leaving white and brown patches and can eat whole leaves if left unchecked.
There are pesticides to control lily beetle although these are more effective on the larvae than the adult. Be careful when spraying in full flower as this could affect pollinating insects.
Many people struggle to kill the lily beetle as they squeak when under stress. They are easy to see and catch, so simple removal and re homing can be an effective remedy. Best way to re-home is to put them in a jar and drive to an unpopulated area to release. They can fly so make sure they are well out of the way.