The leaf issue could be a few problems mate.
1- Leaf rust. This is a fungus and could be the cause.
2- Lock out. Could you have given to much calcium?
3- Deficency. You may have not given enough feed. Possibly nitrogen.
Those would be the 3 main caused buddy π
Personally. I'm going with no 3. Combined with a touch of heat stress π
We are confident, Now you know about the issue you'll get it resolved and back on track in no time π€
Until next time βοΈ
Kind regards
Team-HSO..
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