Use a dehumidifier in damp places. Keep all clothing in a closet with the door shut. Molds grow in garbage containers. Make sure containers are emptied frequently and kept clean. Although indoor plants are not a major source of indoor mold spores, it is wise to limit the number of house plants.
Mold is present in the bark of wood.
If using a wood-burning fireplace, do not store the wood inside. Live Christmas trees should be avoided. A solution of equal parts of household bleach and water will kill mold.