Dear Home Ec 101,
I Want My Blankie
Sleeping bags are notoriously difficult to dry completely. Folding or rolling it up and placing it in a virtually air tight box is rolling out the welcome mat for mildew, the source of your musty smell. Mold and mildew are both fungi that love damp environments. While mold can grow inside walls and ventilation systems, mildew is more often associated with fabrics. This is especially true if you live in a humid environment.
You can add a bag or two of chemical desiccant to the chest. Silica gel is hygroscopic, meaning it absorbs moisture from the air. If your chest is not packed tightly, this should suck up the moisture and reduce the growth of mildew, eliminating the source of smell. When adding items to your chest, be sure they are packed loosely, rather than crammed into every last nook and cranny. If air can’t circulate at all, mildew will have a field day.
One last thing, if the chest has picked up the scent of mildew find some activated charcoal, place this in the chest and lock it up tightly for a a few days. Activated charcoal adsorbs -yes, that is a word, it means attracts chemically, a slightly different mechanism than absorption- some odors. Once the chest itself is fresh smelling, it’s safe to store your dry, clean blankets with the chemical desiccant.
Without mildew in the odor competition any potpourri should be up to the task.
A final few tips:
Line wooden storage boxes and chests with acid free paper.
Roll linen rather than folding.
Cloves, rosemary, thyme, lavender, and dried orange peel all make excellent potpourri, just ensure they do not come in direct contact with any fabric to prevent staining during long term storage.
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