The Stain

• Mildew is a green, often black, stain produced by mold. Mold, commonly called mildew, needs moisture to thrive and thus the mold is common in areas were moisture is prevalent and constant. Bathrooms in most homes are susceptible to mildew, but other portions of the home can fall victim to it as well, depending on the weather and humidity of the area.
  
  

Stained Surfaces

• Mildew thrives in small spaces and is most common between tiles, both in showers, on the walls and on the floor. Mildew can also make its way onto clothing that is left too long or carpets that are allowed to stay damp.
  
  

Commercial Products

• There are many different commercial mildew stain removers. Tilex, for example, is a commercial mildew removal that is aimed at the shower and tile work in homes. It helps to remove the greenish-black mold stains that often appear in bathrooms.
  
  

Natural or home fixes

• While commercial options are viable, there are natural and home remedies that work just as well. A mixture of vinegar, water and salt, mixed together to create a paste, does wonders to remove mildew stains. The vinegar helps neutralize the area while the salt is just abrasive enough to pick up the stains without damaging tiles.
  
  Other home fixes include mixing 1 gallon of water with 1 cup of bleach. The bleach will eat away at the mildew and is believed to help prevent regrowth of the disgusting stains.
  
  

Preventing Mildew

• Mildew can be prevented, on some level, and most homeowners should take steps to prevent mildew growth before it starts. Keep the air circulating. Opening windows is a must. Clearing excess moisture from shower stalls after use also helps to prevent the growth of mildew. Those in extremely humid environments would be advised to invest in dehumidifying machines for rooms that are prone to mold growth.