Things You'll Need
Large bowl or tub
Mild laundry detergent
Nonabrasive cleaning cloth
Keeping wool blankets in humid rooms such as basements or attics makes them susceptible to an unpleasant, musty odor caused by mildew growing in the fabric. Besides the smell, the appearance of black spots is a clear indication of mildew on your wool blanket and requires careful cleaning followed by storing the blanket in a cool, dry place to prevent mildew from reappearing. Hand washing the blanket is the safest way to remove the mildew, as a wash cycle can potentially damage the fabric.
Fill a tub or large bowl with cool water and add 1 cup of mild laundry detergent.
Wipe the wool blanket with a nonabrasive cleaning cloth or pad to remove mildew spots.
Rinse the blanket with cool, running water and squeeze excess moisture out of the fabric.
Hang the blanket on a clothesline outside to air-dry.
Do not use warm water or dry the blanket in a dryer, as it can cause the blanket to shrink.