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Dreaded thrips

Last year, my small and very enclosed urban garden aaas decimated by thrips.

I tried everything: SB invigorator spray which worked very well, but it rained a lot in spring, when I was away, so that didn't help and they had really settled in by the time I returned.

I tried thrip nematodes too - waste of money - though i use slug and weevil nematodes every year and they are brilliant. Unfortunately, thrip nematodes have to make direct contact with the insect, via a spray, so unless you get the buggers as they're flying off, no good.

I don't like spraying chemicals, because my garden, though tiny, has 3 frogs that visit regularly, as well as loads of pollinating insects and birds.

So once the annual insects had died off in late December, the birds were out of sight and the frogs too, I sprayed the whole lot within an inch of its life, to try and kill any eggs lying about.

I also cleared lal fallen annual and hardy perennial leaves ext, which I hadn't done previously, to remove as much diseased stuff as possible.

I've also winter washed my two dwarf acers and dwarf apple tree.

All is looking good, but right up until early December 2014, here in London it was very milk and the blooming' thrips were still flying out in clouds from their favourite nibbles - Japanese anemones, hellebores, hebes....

Some plants were so decimated last year, they've died over the winter (my favourite hebe Pascal image) and many hardy geraniums and anemones which had been glorious in previous years, didn't flower at all in 2014.

I am fed up!

Has anyone else had this problem and found the best solution for it?

Have I missed something crucial? Ought I spray again before Spring perhaps, or do something else?

My tiny garden is my oasis and I was so down when I saw it being chewed up...even a vine weevil infestation and red spider mite infestation were easier to handle than thrips and I managed to get them under control.

Please help image



  • Thanks Edd - never heard of sticky strips! What do I do there and how do they work? Did you find nematodes worked for you? I used the Grow your Own and they made no difference at all, but maybe I wasn't catching them whole or was spraying too infrequently...

  • Thanks Edd. 

    I also tried the mites (which apparently work on red spider mite larvae too), and had no luck with them. It was summer and warm enough, I think. 

    The only nematodes I ever found to use were the type you have to spray directly onto the adults. Never heard of the type you mention, which live in soil...will have a look! So, in theory, if you get all the pupae in time, you ought to be able to eliminate the next generation before it hatches. In an ideal word image

  • Ugh.

    Impressive but, as you say, not cheap and out of my range too. I didn't even know you could get them non-comercially.

    Edd, do you happen to know if the various predatory mites are themselves affected negatively by that SB Invigorator Spray, at all? In case you don't know it, it's an organic, natural and totally safe spray that Ive been using with great results. Controls red spider mite and many other pests, even thrips, when there aren't too many already.

  • Jess, Edd, I use SB invigorator on spider mite - it works by effectively glueing them in place and also acts a foliar feed.  It's recommended to use that first to help quell a heavy infestation before using predator mites.  The problem with SB is that it does wash off, so it's most effective under glass.

    A trowel in the hand is worth a thousand lost under a bush.
  • Hi Bob, yes I use SB with good results against RSM - as Bob says, Edd, SB is a miracle foliar feed that acts additionally by sticking down the mites (works well fir aphid attacks too). I was wondering though Bob- do you happen to know if SB interferes with the mites' movements as well? Maybe I should spray to control thrips, but not spray once I have introduced the mites...

  • Also wonder if there's anything else I should be doing now, in winter, to ensure any thrip eggs overwintering are nuked?

  • Sorry - that should work now.

    I swear by SB Edd - the only problem is when it's really raining a lot and it gets washed off. You need to be persistent.

    Anyone else know what else I could/should be doing in my garden now, to prevent further thrips outbreaks, please?

    They really ruined several plants last summer and I'm keen to be a step ahead this year...thanks.


  • Jess, in response to your earlier query, yes, stop using SB before you introduce predators.  Hopefully the hard frosts we are having this winter will kill any overwintering thrips, eggs, larvae & pupae (did you know they have 6 different stages in their lifecycle?!)  If you had a bad infestation and are keeping any previously affected plants indoors now, I would seriously consider sacrificing them and starting afresh.  I was going to keep some chillies going this winter but decided the risk wasn't worth it.


    A trowel in the hand is worth a thousand lost under a bush.
  • Thank you so much Bob.

    No I'm not keeping any plants, as u mainly only have hardy perennials and evergreens, bulbs, cyclamens and the odd annual. I religiously cleared up all dead leaves this autumn too, as much as I could and sprayed insecticide over all the dormant plants.

    Good idea to stop SB before, I did wonder if the SB would make it harder for predators to move too!

    Can I ask you, do you use any nematodes on your thrips? Was wondering about the effectiveness, since the temperature has to be fairly high before they can e used.

    I hate thrips even more than vine weevil- they ruined my garden last year
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