Rust Color on Camellia Leaves
The plants seem to be healthy but have a rust color on the leaves. I use Seasol once every 8 weeks and have applied slow-release fertilizer on once during watering when needed (due to water restrictions).
Certified GKH Gardening Expert
It sounds like the plant has rust fungus. This article will help: https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm