When you store fabric items, such as curtains, there is a risk of a development of mildew on the curtains. This is because many items such as this are stored in dark places that might have a lot of moisture and humidity in the air, such as a basement, attic or garage. Curtains that are hanging in kitchens, bathrooms or laundry rooms are also at a greater risk of developing a mildew problem. If you find mildew on your curtains, take the time to remove it right away or it could spread and damage your curtains.
Bring your curtains outside if possible. Use a stiff brush to remove any surface mildew that you can.
Add oxygen bleach to hot water in a container that will fit the curtains. You may need to use a utility sink or bathtub.
Place your curtains in the hot water and let them soak for about 30 minutes.
Wash your curtains with regular detergent. Wash in the washing machine if possible or hand wash.
Place your curtains out in the sun to dry. The sunlight can kill any remaining mildew.