Forum home Wildlife gardening

Rosemary beetles

I have a couple of rosemary beetles on my lavender hedge. They don’t seem to be doing much harm at the moment but I’ve read that come the end of summer they will lay eggs and then the family will feast on my lovely lavender bushes and destroy them!! I have just taken out a box hedge because I was fed up of box moth and replaced it with new lavender plants to go with my current lavender hedge. Please tell me I’m not going to have to deal with a plague of these things.
They’re very pretty and I’m happy enough for them to munch away at a bit of my lavender but I want to know if anyone has experience of them becoming a big problem.


  • LG_LG_ Posts: 4,106
    I lost a few plants in the past when I didn't realise what the beetles were - they multiply pretty quickly and significant numbers weaken the plant. Since then, I always remove them when I see them (there are always more than you initially think) and haven't lost any plants since.
    'If you have a garden and a library, you have everything you need.'
    - Cicero
  • LG is right: you see only a couple but there are probably lots more lurking in the shadows. I have them too, have been living in my rosemary and lavender plants for the last couple of years. I am convinced that the only reason my plants are still decent-looking is due to my regular rosemary beetle hunts and culls.
    What I do: I take a big jam jar, hold it under the beetle, shake the stem with the beetle on it and the beetle will drop into the jar. 30 mins like this will usually result in a jar with lots (50? 100? I've never counted them) of beetles trying to crawl out of the jar. (I shake the jar pretty much constantly to keep them from getting out). Then I take a plastic freezer bag, tip all the beetles into the bag, and then (without closing the bag!) I stamp on the bag until all that's left is rosemary beetle mash. It's brutal, but it's the most humane way I have been able to think of.
    I also tried feeding the (live) beetles to my chickens, but they didn't even look at them. I really think I am their only natural enemy ... 

    I'm curious to know if anybody has a more efficient way to deal with these beetles? Mine is quite time consuming.
  • B3B3 Posts: 25,175
    I managed to get them all but it took a couple of weeks. By then, the plant was beyond saving. It was in a pot so it was easy enough not to grow anything they're partial too nearby for a while.
    Do you have sage? They like that too.
    In London. Keen but lazy.
  • AthelasAthelas Posts: 746
    edited June 2021
    @joe.shimmin I'm afraid they can be rather plague like. Still I find it easier (and strangely satisfying) to hand pick them versus dealing with box moth caterpillar, it doesn't feel as overwhelming.

    @foxglovelover I think your method is already quite efficient — at least more efficient than me walking up and down my lavender hedge and picking them off. As soon as I see one (spotted the first one in May this year) I take up regular patrols.

    They don't bother with my rosemary plants, always just the lavender. @B3 good to know they like sage. I have salvias but haven't noticed the beetles on those.

  • joe.shimminjoe.shimmin Posts: 211
    Thanks everyone. 
    That’s a pity, I was hoping you would say that they don’t do much damage and are just nice to look at. I guess I’ll have to go beetle hunting tonight. 
    I hate killing things though. That’s one of the reasons I got fed up with the box. Maybe my daughter would like to keep them in a jar as pets with a few bits of rosemary. 
    Thanks again, Joe
  • joe.shimminjoe.shimmin Posts: 211
    I picked 6 or 7 of the blighters off of my lavender. They are now in a jar with a bit of rosemary and a little water for my daughter to look at. Seemed better than killing them!
  • DovefromaboveDovefromabove Posts: 83,764
    @WonkyWomble has been on the phone this evening cussin’ about the damage rosemary beetles have done to her lavender. 🙄 

    Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.

  • B3B3 Posts: 25,175
    They are a real pest.  If you don't want to kill them, you'll have to stop growing what they like to eat.
    There are many plants I'd like to grow, but I don't if they're slug food.
    It's your decision.
    In London. Keen but lazy.
Sign In or Register to comment.