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Acanthus Spinosus

I am a new member in need of serious help.  I have a large Bears Breeches which usually has about 9 to ten flower spikes, and the leaves are large and luxurious.  It is usually a spectacular plant, or was. For the last 3 years, the leaves have been covered in white powdery mould, it doesn't appear on the flowers though. At the moment 8 flower spikes are appearing, but the leaves are almost dead. I have tried 2 different types of spray for powdery mould, and also white vinegar.  I really don't want to dig it up.  Does anyone have any ideas please. 


  • punkdocpunkdoc Posts: 13,688
    Sounds like powdery mildew. The best treatment is lots of water. The white vinegar will do it no good and might kill it.
    How can you lie there and think of England
    When you don't even know who's in the team

    S.Yorkshire/Derbyshire border
  • fidgetbonesfidgetbones Posts: 16,665
    Mine get like that towards the end of summer if they are too dry. They are thirsty beasts, water them .  I think they are impossible to kill without glyphosate. I cut off excess, and they still come back the following year.
  • JennyJJennyJ Posts: 8,789
    Mine are covered in powdery mildew already, because we've had an extremely dry spring and I concentrate my watering efforts on containers and newly planted things. It usually doesn't strike until later in the summer. It's unlikely to kill the plants, they are tough stuff and grow back from the tiniest bit of root if you try to dig them up.
    If you're prepared to lose the flowers, you could chop the lot back to ground level and keep them well-watered and they'll be back very quickly (but might not flower again this year). You could cut off the leaves and leave the flower spikes but it might look odd.
    Doncaster, South Yorkshire. Soil type: sandy, well-drained
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