I will try to get a picture of it up somewhere but I have these white
> patches on my zucchini and cucumber leaves???
>
> Any ideas as to what it is or what to do?
>
> Thanks
> d
Fungus amongus
I searched
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using the term "zucchini fungus" and came up with nearly 3,000 possibilities, among the first 10 was this one. It is not 'authoritative' but should get you started.
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both zukes and cukes are from the cucurbit family and susceptible to pretty much the same diseases. What you have is probably powdery mildew. Do a search on "powdery mildew" for the treatment. Bill