Lily beetle

in : Problems: Flowers

Symptoms

Lily leaves are shredded and may be covered in brown-black droppings.
Find it on lilies, fritillaries and Solomon's seal
Time to act spring, summer, autumn

Problem categories

Overview

Scarlet beetles (6mm - 8mm long) with black heads eat the leaves, flowers and seedpods of lilies and other members of the lily family. Don't mistake them for ladybirds. Between April and September the beetles lay eggs on the undersides of leaves. After a week they hatch into reddish-brown maggot-like grubs, and feed on the same parts of the plant as the parents. Possibly to deter predators or disguise themselves, the larvae cover themselves in their own wet, black excrement.
Solution
Lily leaves are shredded and may be covered in brown-black droppings.
Organic
Pick off the grubs and adults as soon as you see them. The adults will drop to the ground at the slightest touch, so spread newspaper under the plants to catch them. Be quick and crush them under foot or they'll fly off.
Chemical
At the first sign of attack, spray plants with imidacloprid, thiacloprid or sunflower oil. Treatment is more effective on larvae than adults.

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Talkback: Lily beetle
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kaycurtis 24/11/2011 at 15:27

Goodness me , the dreaded Lily beetle along with all the other things that attack our lovely plants, well if you water the plants with vine weeval killer it does help to protect them also against Lily beetles, killing two pests for the price of one!!

alan 24/11/2011 at 15:27

every year i have to pick these little demons off my lillies their little grubs are a bit grim to remove but using something as easy to obtain as sunflower oil will make my life easier

Daisy005 24/11/2011 at 15:27

Thank you for the advise I will be trying the sunflower oil! I have read that the insecticide, imidacloprid, you have recommended is possibly linked to honeybee colony collapse - is this true?

I am off to stamp on a few lily beetles and spray!

Anorthcott 24/11/2011 at 15:28

Have had this problem for 2 years now and will try the sunflower oil. Does anything remain on the plant and go down into the bulb ready to infest next season?

lilymaewebster 24/11/2011 at 15:28

last year was my first infestation which i found on my himalayan lilies (cardiocrinums) and hemoracallis. luckily i caught it in time but i gave an oriental lily to my neighbour a couple of years ago which had been completely decimated. i had noticed that the lily wasnt flourishing as it had done in the past and then suddenly it completely died. do you think my lily beetle problem started with the plant that i gave to my neighbour? my lilies completely survived this attack.

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