Help - What's on my Sprouts??

[WhatKatyGrew]

I've just been up to my plot to squash some cabbage white eggs on my sprouts. While I was doing it I noticed some of the leaves had some white powdery patches on - what is it? Is it going to eat all my sprouts?? Do I need to get rid of it??? If so, how?????

[rustylady]

Have you got a picture? Are the patches on the top or the bottom of the leaves?

[WhatKatyGrew]

They are on the top of the leaves, I'll pop back tomorrow with my camera.

[kerryp]

ive got patches that sound like this on my courgette plants as well so will be interested in what they are....