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Should I remove my Aster?

I have this Aster having some nice blooms over Autumn. There were new blooms growing after the first wave but then one day I noted there was something like powdery mildew covering the top of the plant. The new blooms appear to have stop growing, and the inner part of the leaves and stems turn black. Some stems turn yellow. Is this normal for Aster is a deciduous plant which will lose its leaves and stems in winter, or is it dying? There has been quite a lot of rain recently. I’m not sure if there might be too much moisture stayed on the plant causing its blackening state.

(PS: I just realised when I took the photos this morning that there are some new shoots appear from the soil.)


  • I would cut it right back and it will come back beautifully. What you are describing is typical as autumn damp sets in. 
  • punkdocpunkdoc Sheffield, Derbyshire border.Posts: 13,027
    Unfortunately some Asters are very prone to getting mildew and are likely to develop it every year.
    There are ashtrays of emulsion,
    for the fag ends of the aristocracy.
  • AnniDAnniD South West UKPosts: 11,011
    Liz is correct, cut them back now. They will start to grow back in the Spring. They are notorious for mildew, but a lot depends on the variety. 
    Some info here that you might find useful.
  • GardenerSuzeGardenerSuze I garden in South Notts on an improved clay soil Posts: 3,118
    Aster Novi angliae seem to be less prone to mildew than A novae belgii. Should be using the new name Symphyotrichun?
    The most serious gardening I do would seem very strange to an onlooker,for it involves hours of walking round in circles,apparently doing nothing. Helen Dillon.
  • The New England (Nova Angliae) asters are supposed to be less susceptible. I have tended to favour them as it is often very wet here and haven't had any problems with  mildew. Good air circulation also helps though and there hasn't been any shortage of that either recently!
  • nutcutletnutcutlet PeterboroughPosts: 26,869
    If it's a nice one I'd give it another chance but I'd get rid of anything that looked as bad as that more than once
  • JennyJJennyJ DoncasterPosts: 7,706
    If it doesn't develop mildew until this late in the season, that's pretty good for an aster. No need to get rid of it if it looks good while it's in flower. Cut it right back to ground level. The new basal shoots that you can see might not come to anything, but it should produce lots more next year.
  • FairygirlFairygirl west central ScotlandPosts: 49,147
    Mine don't really get mildew, but that's down to climate, and perhaps variety. Some are definitely more prone than others, as @Buttercupdays and @punkdoc say. 
    It's not bonny, but it depends on how much you see it at this time of year, as opposed to when it's in full flow, and whether you think it's worth persevering with. I'm like @nutcutlet - if something isn't doing the job I want, it gets chucked.
    It's a hard school here... ;)
    It's a place where beautiful isn't enough of a word....

  • HeyawcHeyawc Posts: 11
    Thank you everyone for the advice! It was great when it’s in full flower, so I may give it another chance and see how it comes back in spring. Learning to be a good gardener everyday :smile:
  • JennyJJennyJ DoncasterPosts: 7,706
    I've just noticed that my Aster (or Sympho-wotsit) "Little Carlow" (which don't really suffer from mildew) have now developed the yellow stems and black leaves, possibly in response to a few chilly nights. It's part of the late autumn colour, so I'll leave them until they've lost the colour or fallen over.
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