On 22/04/2015 10:51, Michael Uplawski wrote:
Hi all.

On Mon, 20 Apr 2015 20:47:12 +0100,
Bill P wrote:
I grow my tomatoes in a cold greenhouse, I often get white patches on
the leaves, but this year a quarter of my plants are effected.

It is powdery mildew, as far as I know.
http://www.tomatodirt.com/powdery-mi...-tomatoes.html
http://tomatodiseasehelp.com/powdery-mildew

Funny enough, I though to plan my tomatoes in a greenhouse to *avoid*
this kind of problem but learn today, that it is „(...) more common in
commercial tomato fields and greenhouses than in the home garden (...)”.

Okay, I know nothing and so does everybody else.

The above referenced pages contain some hints on how to treat the plants
affected by the mildew, but from what I have seen here and elsewhere,
this may work. Or not.

Good luck.

Michael

I thought
it could be something to do with the extreme temperature we have been
getting this month.



It is either very hot sunshine or freezing cold.

Any ideas would be gratefully received.


I have seedlings that went white a day after putting them outside in a
cold frame. I think it must have been the shock because, back indoors,
they're turning green again