My Pyracantha shows a diffused discolored contour of its leaves. Some have also dark dots on the discolouration area. The center remains green.
Fertilisation is done correctly with a combination of Biogold monthly and, Humic acids + Aminoacids + Kelp every other week. Soil is Akadamaa and pumice. Light is abundant as they are kept in plain sun on the terrace. Does anyone know what it could be?