Sooty Mold is a form of fungus that grows on the sugary honeydew secreted by AphidsSee a picture, learn to identify, and read about Aphid houseplant pests in the Glossary of Houseplant411.com., scaleSoft Brown Scale plant pests are the most common scale that attack indoor houseplants, especially ficus tress, various ivy varieties, spider plants, ferns, aralia, and schefflera. The scale plant pests appear as small, bumpy, brown spots that may appear to move. As the scale plant pest sucks on the sap of the plant, it secretes a sticky substance called "honeydew." The honeydew attracts black mildew. Because of the shell-like exterior, sprays are only partially effective against scale. Wipe off the lines of brown oval bumps with your finger, a cloth, or a child’s toothbrush then spray the plant with Neem Oil or a houseplant insecticide. You can use the non-toxic, easily made Green Solution to clean off the black mildew.s, the whiteflyLearn how to identify and treat the plant pest Whiteflies at https://www.houseplant411.com/glossary/whiteflies how to identify and treat, and other insects that suck the sap from plants. Sooty Mold is an unsightly black powder that can quickly coat the leaves of a plant in just a few weeks. The fungus itself doesn’t really harm the plant; it just ruins the plant’s appearance. Sooty Mold can be prevented by getting rid of the insects that secret the honeydew that attracts the Sooty Mold.