Sooty Mold is a common black mold found on a wide variety of plants. It is almost always an indication of an insect infestation. It is caused by any of several species of fungi that grow on the sugary material (honeydew) left on plants by aphids, whiteflies or other insects that suck sap from the plant. Sooty mold is unsightly but if fairly harmless because it doesn’t attack the leaf directly. Once the insect problem is under control, rain will eventually wash off the sooty mold.
