How To · Fashion · Grooming Basics
Store wool sweaters without inviting moths to dinner
Moths aren't after your sweaters for fashion advice—they're after the protein in wool. Stop them before they start with these five essential storage moves.
5 min read · IrisWool moths don't discriminate. A $300 merino crewneck gets the same treatment as a thrifted cardigan. The larvae eat keratin—the protein that makes wool, wool—and they're remarkably efficient about it. One female can lay hundreds of eggs in your closet, and you won't notice damage until it's too late.
The good news: moth prevention is straightforward and doesn't require toxic chemicals or paranoia. It's about three things: cleanliness, barriers, and active deterrents. Do these five steps before you pack away your sweaters for the season, and you'll open that storage box to intact knitwear, not moth holes.
Cleanliness is your first line of defense. Moths target sweaters with food residue, sweat, or skin cells already embedded in the fibers.
What you'll need.
- 01Wool-specific detergent
- 02Clean towels or mesh drying rack
- 03Airtight plastic storage bins with lids
- 04Acid-free tissue paper
- 05Cedar blocks or lavender sachets
- 06Silica gel packets (optional)
- 07Permanent marker for labeling
Step one · 2 minutes
Wash or air-freshen every sweater before storage
Moths are attracted to organic matter—sweat, food particles, dead skin cells. A single wearing creates enough residue to draw them in. Wash your sweaters in cool water with wool-specific detergent, or if they're lightly worn, hang them outside in direct sunlight for 2–3 hours. Sunlight kills moth eggs and larvae. Never store a sweater that's been worn without at least airing it out first.
If you hand-wash, rinse twice to remove all detergent residue, which can also attract pests.
Step two · 3 minutes
Dry completely before folding
Moisture invites mold and mildew, which can damage wool just as effectively as moths. Lay sweaters flat on a clean, dry towel or mesh drying rack in a well-ventilated space. Never hang wet wool—it stretches. Allow at least 24 hours for complete drying. Check the underarms and collar, where moisture lingers longest. Damp sweaters are a storage liability.
Use a fan to speed drying without direct heat, which can felt wool.
Step three · 4 minutes
Fold and stack in airtight containers
Fold each sweater neatly and place it in a plastic storage bin with a tight-sealing lid. Airtight containers create a barrier that moths can't penetrate. Avoid cardboard boxes, which moths can chew through and which absorb moisture. Label your bins by color or type so you know what's inside without opening them repeatedly. Stack bins in a cool, dry closet or under a bed—not in a basement or attic, where temperature and humidity fluctuate.
Place acid-free tissue paper between layers to prevent creasing and add an extra protective layer.
Step four · 3 minutes
Add cedar blocks or lavender sachets
Cedar is the gold standard for moth prevention. Its natural oils repel moths and their larvae. Place 2–3 cedar blocks or cedar chips in each storage bin. Lavender sachets work similarly, though they're slightly less potent. You can also use dried rosemary or thyme. These aren't just pleasant-smelling; they're functional deterrents. Replace cedar blocks every 6–12 months as their potency fades, or sand them lightly to refresh the scent.
Don't use mothballs. They contain naphthalene or paradichlorobenzene, which are toxic and leave a chemical smell that's nearly impossible to remove from wool.
Step five · 3 minutes
Store in a cool, dry, dark location
Temperature and light matter. Moths thrive in warm, humid environments and are less active in cool spaces. Store your bins in a closet, under a bed, or in a climate-controlled storage area—not near a window where sunlight and heat can penetrate. Keep storage areas away from pipes, vents, and areas prone to moisture. Check your bins every 2–3 months, even if they're sealed. A quick visual inspection catches any problems early.
If you live in a particularly humid climate, add a small silica gel packet to each bin to absorb excess moisture.
Step six · ongoing
Rotate and inspect seasonally
Don't forget about your stored sweaters. Every season, open your bins and do a quick inspection for any signs of damage or pest activity. If you notice small holes, webbing, or a musty smell, act immediately. Remove the affected sweater and wash it in hot water. Vacuum out your storage bin thoroughly, replace cedar blocks, and consider moving storage to a different location. Rotation also prevents permanent creasing from long-term storage.
Take photos of your sweaters before storage. If damage occurs, you'll have documentation for insurance purposes.
How to know it works
When you open your storage bins months later, your sweaters should look and smell exactly as you left them. No holes, no webbing, no musty odor. The fibers should be intact, the color unchanged, and the fit uncompromised. Proper storage is invisible—you only notice it when it fails.
Questions at the mirror.
I found a hole in my sweater after storage. Is it ruined?
Not necessarily. Small moth holes can be professionally darned by a skilled tailor, especially if the damage is localized. Wash the sweater immediately in hot water to kill any remaining larvae, then assess the damage. For larger holes or multiple damaged areas, a professional repair might not be cost-effective, but small damage is often fixable.
Can I use mothballs instead of cedar?
Avoid mothballs. They contain toxic chemicals that are harmful to inhale and nearly impossible to remove from wool. Cedar and lavender are safer, more pleasant-smelling alternatives that work just as well.
What if my storage area is humid or damp?
Add silica gel packets to your bins and consider moving storage to a drier location. If your closet or under-bed space is consistently damp, use a small dehumidifier nearby. Moisture is as damaging as moths—it causes mold and mildew that can permanently discolor or weaken wool fibers.
How often should I replace cedar blocks?
Cedar's scent fades over 6–12 months, but its effectiveness lasts longer. Replace blocks annually or when you no longer smell cedar when opening the bin. You can also lightly sand the surface of used blocks to refresh their scent and extend their life by a few months.