Molds come in all sizes, shapes, textures, and colors, while mildew is typically characterized by a white or gray powdery fungus.

When you see “mildew,” you are most likely seeing a mold that is in the Ascomycota division, which tends to be lighter in color and more powdery in texture. (You may have heard the term “powdery mildew,” which is a plant disease caused by Ascomycota fungi.)