Botrytis, or gray mold as it is commonly called, is a fungus that attacks the leaves, flowers, stems, and rhizomes of house plants. It first appears as a round brown or gray spot that gradually turns into a mass of fuzzy gray spores. This is where the nickname, gray mold, comes from. Prevent botrytis by quickly removing all dead or dying leaves and flowers that can serve as a breeding grounds. Keep water off of the leaves and provide good air circulation around plants. If a plant becomes infected with Gray Mold, trim off the diseased areas, remove any soil that has mold on it, and spray with a commercial FungicideLearn what fungicides are and how they are used to treat fungal and bacterial plant infections.. If you are adverse to chemicals you can try this homemade remedy. Put a tablespoon or two of baking soda in a spray bottle, add a teaspoon or two of mineral oil, and fill with water. Shake well and spray all parts of the plant. Botrytis often attacks the flower buds of Cyclamen, Begonias, African Violets, Lilies, and Geraniums.