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16 messages
18/10/2013 at 22:27

Hi all I have one of these in my garden and it has developed a horrible mildew.

What can I do with it now to help stop this coming on the plant next year?

Many thanks

18/10/2013 at 22:42

Asters are prone to mildew when they get too dry.   Keep it evenly watered and it should be ok next year.

18/10/2013 at 22:46

I only planted it this year and it was terribly rootbound when I got it out of the pot. I guess it must have dried out quite a bit at the garden centre in that tiny pot 

It's in a nice sunny spot now with moist soil so I guess it should be fine. Should I cut it down now to to minimize the risk of it re-appearing next year?

18/10/2013 at 22:57

Yes, cut it down now then next year keep it moist and it should be fine.

18/10/2013 at 23:00

Thanks a lot for the advice

It's getting the chop tomorrow 

18/10/2013 at 23:26

I would wait until it has finished flowering.

18/10/2013 at 23:27

It has finished flowering. Just a couple of flowers left that look a bit tatty 

19/10/2013 at 00:23

I would do more than that matt.  I would dig it up and loosen those roots.  Unwind them and spread them out.  Before replanting dig in plenty of compost, dried manure, etc and water well.  Can you give it a slightly less sunny spot too?

Mildew is a regular problem with most asters and you can apply a fungicide but if you can provide a humous rich, moisture retentive soil the risk of powdery mildew is greatly reduced.  There are a couple of asters that do not get mildew, viz., little Carlow and Frikartii Monch.  These are much better, longer flowerimg asters too.  

19/10/2013 at 07:17

I agree with Verdun, he said

"..... I would dig it up and loosen those roots.  Unwind them and spread them out.  Before replanting dig in plenty of compost, dried manure, etc and water well.  Can you give it a slightly less sunny spot too?...."

That's exactly what I would do, and now is the perfect time to do it.   I would only add .... before digging it up give it a through soaking. 

19/10/2013 at 09:10

Oh yes dove!  Forgot that .......in a bucket for 30 minutes 

19/10/2013 at 09:17

I already did all this before planting. The plant is at the front of 1 of my raised beds which isnt getting much sun now but gets plenty in the Spring and Summer

19/10/2013 at 09:18

But I will check to make sure the roots have started to spread from the rootball

19/10/2013 at 09:22

Well then it's probably just it's natural susceptibility coupled with a particuarly dry summer.  Increase the humus content of the bed, mulch in the spring to retain moisture and water regularly, and just accept that it's prone to mildew but lovely for all that.  

If it gets a bad attack early in the season and looks really unsightly I'd cut it back  and give it a sprinkling of potash and a watering, and then if we get an Indian Summer it may well manage another flowering period.

19/10/2013 at 09:24

Thanks for the advice guys

I will go and see what I can do with it before the thunderstorms arrive! :P

19/10/2013 at 09:59

The roots are spreading nicely through the soil which is a good sign, I cut down all the foliage and removed any bits from the soil then gave it a good mulch.

Lets hope it puts on a good show next year

19/10/2013 at 10:02

Sounds promising - green fingers and thumbs crossed 

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