disease on globe thistles echinops, moths blackfly?

Discussion in 'Pests, Diseases and Cures' started by berarde, Jun 22, 2025.

  1. berarde

    berarde Apprentice Gardener

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    The globe thistles at our community garden and my garden are stunted with shrivelled and deformed leaves.

    Online search doesn't mention this and they are largely tough and disease free.

    They are stunted in growth and some developing globes are small.

    As per the photos some of the the leaves are white some curled upside down. There look to be a few bits of webbing but also one of them has a blackfly.

    Any ideas appreciated as well as suggestions for treatment paticularly as the internet hasn't come across this.
     

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  2. Pete8

    Pete8 Total Gardener

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    I used to grow them and often they'd get mullered by blackfly.
    Whilst they are very tolerant of drought mine often suffered after many weeks of no rain in the summer which is typical here. The plant gets weakened, then the bugs move in to take advantage.
    Ladybirds will eventually turn up and eat them, but by then a lot of damage has been done.
    You could use a contact insecticide such as pyrethrum at a time when bees etc are not active or blast them away with a jet from a hose - the foliage is very tolerant, but you may not have a hose in that location.

    The webbing may indicate that it also has spider mites which are not easy to deal with. Being arachnids (related to spiders) few insecticides will have any effect.
    Neem oil may work
     
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    • NigelJ

      NigelJ Total Gardener

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      @berarde
      It's a tad tricky from your low res pictures to see whats happening. I can see that somebody cycles and the fluorescent strip to stop the trousers snagging looks good.
      More seriously yes there is black fly and could the webbing be from red spider mite?
      Has it been very dry and warm where you garden, because red spider mite likes hot dry conditions, you might need a hand lens to see the mites.
      I presume they are growing in the ground, I would start with a good water, spray the plant with water to knock the blackfly off, then give them a feed.
      My Echinops tienshanicum is growing as well as ever, on it's way to 6 ft and has never had problems with blackfly.
       
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      • Thevictorian

        Thevictorian Super Gardener

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        Every year ours, and we have dozens, get hamered by blackfly but it doesn't normally slow them down much. This year they have had aphids as well I think which does distort the leaves (it seems to have been a bad year, from a gardeners perspective, for aphids).
        Ours also get a few leaves folded over and stuck together with webs but this is relatively few and far between, being caused by garden spiders. If it's every leaf or over a large part of the plant it's probably more sinister and likely spider mites.
         
      • Adam I

        Adam I Super Gardener

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        mine was covered in aphids too. I sprayed them off and it helped. Did worry about spraying ladybugs off it :scratch:

        I planted them because the flowers are supposed to be amazing for bees, maybe they are best as a food source for predators instead...
         
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        • NigelJ

          NigelJ Total Gardener

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          My E tienshanicum when it flowers in about 4 weeks will be a mass of different bees, flies and hoverflies from dawn till dusk.
           
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          • Thevictorian

            Thevictorian Super Gardener

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            They are a magnet for pollinators but predators love them as well. I always find crab spiders love to hunt on them.
             
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