Ahhh, my parents had the same problem when they visited Sweden. The problem is the Bonsai trees are being choked by the smog in the air. Africa is a very big industrial based society, and the pollution in the air is making your plants suffocate.

To rectify this, simply smother your plants in natural honey, and I mean natural, BECAUSE IF I FIND YOU USING ARTIFICIAL SHIT ON THEM PLANTS I'LL DESTROY YOU!