Why do rust-colored patches appear on camellia leaves? What should I do if the camellia leaves have rust spots and are falling off?

The back of the leaves is rusty and the leaves are everted. The following symptoms of rust on camellia leaves are not consistent with what you said. They are all rusty on both sides, and yours is only on the back of the leaf. Therefore, everything is ruled out

The closest case to what you mentioned is Camellia "rust tick". This disease only causes rust on the back side of the leaves and the leaves are everted, which is close to what you said. You don't have a picture, we all rely on the experience accumulated in the breeding process for many years to answer.

Rust on the back of the leaves is caused by the insects using their piercing-sucking mouthparts to pierce the leaves and suck the juice from the leaves. If the needle is sucking out, the leaves will turn outwards and twist along with the air evacuation principle. As for the rust color, it is caused by insect secretions infecting the wounds on the leaves. Suggestion: Since most insecticides use external suction for contact killing, it is difficult to take care of both eggs and adults! Only the medicine in the picture below, which works on the principle of internal suction and contact with the stomach, can treat both insects and eggs

After spring, the soil is changed and the pots are disinfected. Now it is best to put "Earthworm Pill" in the pots or root-irrigation with Avi bacteria. white.

Through our introduction, I believe everyone has a deeper understanding of what causes rust-colored spots on camellia leaves and what to do if camellia leaves have rust spots and drop leaves.