Homeowners often focus on removing mold from their bathroom walls or basement carpets, but mold is also capable of growing on fabric and textiles in your home. This is especially true of felt, which can hold a lot of moisture inside. Mold needs moisture to survive and will begin to grow on and decay damp felt. Prevent this by storing fabric in dry areas that receive a lot of ventilation. Dry out felt pieces if they accidentally get wet. If your fabric storage is in a damp basement, install a dehumidifier to remove the excess moisture from the air and from the fabric.
Remove mold as soon as possible, as it will actually decay felt fabric.
Add just enough salt to 1 tbsp. lemon juice to make a thick paste that is the same consistency as toothpaste.
Smear the paste over the mold stains.
Let the paste sit in the sun for 10 minutes if the felt is white. If it is not, skip this step as the process could remove some of the color.
Rub the paste into the mold stain until it is gone.
Launder the felt as normal.