I grow lemon for several years, but this year the new, already expanded leaves begin to dry up from the top or sides and fall down! Any ideas why?
Why Lemon Leaves Fall Down?
Certified GKH Gardening Expert
It is possible that this is insect damage, likely mites. They can be very small and hard to spot. You can check for them by holding a white piece of paper under some of the affected leaves and gently shaking the branch. If there are mites, you will see specks on the paper. They can be treated with a miticide, like neem oil.
Another less likely possibility is that it is a fungus and a fungicide should clear it up. If you use neem oil, it is both a fungicide and a miticide and will treat both possible issues with one solution.