|My hibiscus plant is covered in black spots then leaves turn yellow before falling off. I'm not familiar with disease or how to treat it.|
|Leaf spots are caused by fungi or bacteria. Brown or black spots and patches may be either ragged or circular, with a water soaked or yellow-edged appearance. Insects, rain, dirty garden tools, or even people can help its spread.
To prevent and control, remove infected leaves when the plant is dry. Leaves that collect around the base of the plant should be raked up and disposed of. Avoid overhead irrigation if possible; water should be directed at soil level. For fungal leaf spots, use a garden fungicide, according to label directions.
Best wishes with your hibiscus!