our gardenia bush has black film on leaves, what could this be

Question

Our gardenia has black film on leaves. What could this be?

Answer 1

It sounds like you have sooty mold. It is normally a sign of a pest infestations. I recommend treating the mold and pests with neem oil. Here is some information that can help you:
https://www.gardeningknowhow.com/plant-problems/disease/how-to-get-rid-of-sooty-mold.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm