The Garden Community for Garden Lovers

What are these caterpillers on my lilly?

Hampshire, United Kingdom Gb

My lilly has been attacked by caterpillars. At least that’s what I think they are. They can only been described as like black snot and when you touch them they disintegrate. How can I get rid of them? They have eaten all the leaves and sent them light green. Most of the plant is dying. Help please.
Thank you all for your answers. You have been very helpful. I have since killed most of the horrible beetles and just hope the plant recovers in time for next year.



This sounds like the larvae of the dreaded lily beetle. The beetle is bright red. Inspect your plant regularly, removing and squashing any that you find. The caterpillars are best removed with damp kitchen paper. They are certainly revolting! If the problem recurs year after year, it's as well to throw out your lilies and have a gap of a few years before trying to grow them again. I have just done this and so far have not had any trouble this year.

30 Jun, 2009


The bugs cover themselves with their own excrement as a disguise. RHS say infested plants can be sprayed with imidacloprid + sunflower oil (Bayer Provado Ultimate Bug Killer concentrate), acetamiprid (Scotts Bug Clear Ultra concentrate) or thiacloprid (Provado Ultimate Bug Killer Ready To Use). The larvae are more susceptible to insecticides than the adults.

1 Jul, 2009


I hate to disagree, Pennyfarthing, but as the Lily beetle is now a menace over most of the UK, I don't think that taking a break for a year would necessarily help - I would just carry on growing lilies and keep your eyes peeled every day, squishing the beetles as they appear. They also attack fritillaries.

Spraying is also an option, as Wagger says, if you don't mind using chemicals - I know some people don't like them.

1 Jul, 2009


Have to agree with Spritzhenry. There was no garden at all here when we arrived in 2003 (in a very rural location in France about a kilometre from the nearest neighbour) yet the dreaded lily beetles arrived the next summer!
Don't use nasty chemicals, but just keep squishing (red beetles and the grubs.) Once you've done it a few times you can overcome any squeamishness. This is the best way to control pests like this, and we have managed to eradicate Colorado beetles on potatoes in the same way, without harming beneficial insects.

1 Jul, 2009


hi spritzhenry and Bertiefox, I didn't mean to imply that the 4 gap years I left meant I wouldn't get the wretched beetle ever again! I wish!
It was just that I got so fed up that I threw all my lilies away and told myself I wouldn't bother any more! However, I have some new ones this year and so far, touch wood, they haven't been affected. I keep a sharp eye on them because I can't believe my luck! From being inundated year after year I have none at present.
I couldn't cope with squashing between finger and thumb so I used to knock the beetles into a yogurt pot and then tip them out and tread on them. I used the provado spray on the larvae Hope this clarifies my first post!

1 Jul, 2009


Yes, it does! :-)

I had to smile at your yogurt pot ploy - I get the pots with the lilies in, and upend each one carefully over the empty wheelbarrow - the beetles fall off and then - a big stone dispatches them! LOL.

4 Jul, 2009

How do I say thanks?

Answer question


Not found an answer?