Mold vs. Mildew

The Difference Between Mold & Mildew

Mold and mildew are both types of fungi, but they have striking differences when it comes to size, color, and texture.  Both mold and mildew are attracted to moist, warm areas where they can grow, such as food, walls, ceilings, showers, etc.


Mold is a fungi that contains multiple identical nuclei and can appear almost “fuzzy”.  It is often blue, black, or green, with a musty smell, and is often the result of a larger infestation.  Mold obtains its energy from food and other organic matter, but is only visible to the naked eye when colonies start growing.

Mildew is a specific kind of surface mold that can easily be identified as a patch of gray, white, or yellow fungus near the surface of the moist area.  It usually grows in a flat pattern and may appear powdery or downy.  It is usually found on host plants such as beans, maize, potato, tomato, rice, etc.  It can also grow anywhere that the moisture content is high, such as clothing, shower curtains, and window sills.


Mold can cause severe structural damage to homes over time, along with numerous health problems, like respiratory issues.  Some common health effects to look out for when exposed to mold are difficulty breathing, coughing, sneezing, sore throat, migraines, sinus infections, pneumonia, allergic reactions, rashes or hives, inflammation and pain in the joints, and extreme fatigue.

Mildew can cause damage to plants and crops.  It can also cause health problems, including respiratory problems, difficulty breathing, coughing, sore throat, and headaches.  Although mildew is not generally harmful, it still can be visually unappealing and foul smelling.

Common Types


  • Acremonium - is a common household mold, frequently found indoors.  It can cause allergic reactions and respiratory infections.
  • Aspergillus- often grows on drywall that has sustained water damage and produces a characteristic musty odor.
  • Penicillium- often grows on materials that have been damaged by water and it spreads quickly from one home to another.


  • Peronospora - belongs to the class of water molds and often grows on plants.
  • Blumeria - is a fungus that causes powdery mildew on grasses.
  • Podosphaera - is a plant pathogen that produces a powdery mildew on members of the rose family.

The best way to keep mold and mildew from growing in your home is to eliminate as much moisture from your house as possible.  Fix any leaks, tightly seal doors and windows from water, and use a ventilation system for any steam.  Mildew can often be removed with just a cleaner and a little bit of elbow grease. Mold, on the other hand, should be professionally removed.

If you have a run in with moisture in your home, contact AAA Flood Drying at (978) 392-1895 for a quick cleanup service.