By Squiral
Lincolnshire,
United Kingdom 
on a couple of my tubbed roses i have this mould look on the leaves, but when you go to wipe it off it doesn't come off powdery like talcum powder when you under water the plant. The leaf itself feels like its sweating, has anyone else had this problem before.
On plant
Albertine & Excelsa.
5 Jul, 2011
Answers
Tugbrethil, thanks for the reply, the leaves feel wet to the touch, like its been raining, but not sticky. I have sprayed it with a fungicide but it just seems to be spreading like mad.
6 Jul, 2011
Wow! I've never heard of leaves being wet like that, Squiral! Is it possible that your neighbor is hosing them down when you're not looking...but that should only stay wet for an hour or so. Hmmm, I'm flummoxed, then! If something is wetting them down frequently, then the white could be hard water deposits.
6 Jul, 2011
thanks for getting back so quickly, you could be right about the hard water, thats something i didnt think of.
6 Jul, 2011
Previous question
« I have a tree that looks like a greengage. How can I be sure fruit is safe to eat?...
Next question
I don't know about the sweating part, but the rest sounds like powdery mildew, one of the few fungi that likes dry weather. Fortunately there are a number of fungicides, both chemical and organic, to take care of that problem. By "sweating", do you mean that the leaf is sticky?
6 Jul, 2011