Q.I have a lot of camellias in my garden (sasanquas as a border and 2 other trees in a separate area. But they all are sick with grey mo
ttled leaves. I have sprayed a few times but this hasn’t done anything. I am now thinking of cutting right back, hoping for a healthier growth of leaves. What do you think? Sorry, don’t know how to download photos to send to you.

Certified GKH Gardening Expert
It's hard to say what may be causing this, but I think you're on the right track with the idea of cutting them back. So, first, here's an article to help you figure out what's wrong with your plants:
https://www.gardeningknowhow.com/ornamental/flowers/camellia/identifying-and-fixing-problems-with-camellias.htm
and, here's another to help you know how to prune them:
https://www.gardeningknowhow.com/ornamental/flowers/camellia/pruning-camellias-how-to-prune-a-camellia-plant.htm