Annettegutk, unfortunately a garden expert is NOT an Adenium expert!
These guys are famous for growing huge plants in small containers. I would agree that it needs adjustment time.
Fertilizers are meant to support good growth in my opinion, not create it!
Systemic, I guess you are talking about insect control is not a good idea. There may not be any insects involved. I see loads of new green growth coming. That is encouraging!
I would follow the above suggestions.
Tarev and Baja have impressed me with their knowledge on numerous occasions! I would take their advice!!
