Hello! The symptoms in the attached pictures are similar to those caused by a leaf spot disease. In this case, it is recommended to remove the affected leaves with well sharpened and previously disinfected tools () and destroy them by burning (they should not be left on the substrate). Subsequently, it is recommended to carry out two treatments at 7 days intervals with in a dose of 10 ml solution / 10 l water. At the same time as the foliar treatment, it is recommended to apply 2-3 times a special fertilizer such as , which helps to maintain the general health and regeneration capacity of the plants.
Afterwards, 10-12 days after the treatments, it is recommended to apply an organic foliar fertilizer spray, which contributes to the healthy growth of the plants and strengthens them after certain periods of stress, such as .
Additionally, more information on the care of this species can be found in our article: Euonymus, planting guide and care work.