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foxglove77 · 22-07-2008, 09:35 PM

Quote:

Originally Posted by Alan Sung

"foxglove77" wrote in message
...

I have had a terrible fungal prioblem in my garden this year. I think
its mainly powdery mildew that has affected my clematis, of which I
have had to cut down about 5. It has also affected my honeysuckle, my
continus coggygria or "smoke bush" my rhododendron, and about 3 of my
other shrubs.

I have read that in clematis it can be caused by too much darkness and
moisture, but then in the same breath that it could be caused by
dryness at the roots, what am I to believe? At the time I was giving
them a thorough watering so believed it to be over watering. All I can
do it cut all these plants back hard and hope it doesn't come back
again. It seems to be an epidemic!

If it is really powdery mildew, then it's really more of an aesthetic
problem than it is deadly to your plants. Cutting back isn't really
necessary. The spores are in the air and high humidity and high temperature
tends to encourage powdery mildew. Google "powdery mildew treatment" and
you'll see all sorts of chemicals and organic cocktails.

-al sung
Rapid Realm Technology, Inc.
Hopkinton, MA
(Zone 6a)

I've heard of a cocktail of baking soda and horticultural oil added to water. I am not actually sure where to get "horticultural oil" and infact that is what it will be labelled in the shops, or whether it comes under a different generic name?