How to Store Wool So Moths Never Get It

A sweater comes out of summer storage with a row of holes along the collar, and the moths that did it are long gone. The adult webbing clothes moth does not eat wool at all — the damage is larval, and the larvae want three things at once: keratin, darkness, and months of undisturbed time. A folded sweater in a closed drawer is all three in one place. Storage is therefore not about keeping moths away from the room; it is about making sure nothing edible goes into the container and nothing living gets sealed in with it.

Wash first — the soil is the attractant

Larvae do not feed on clean wool with any enthusiasm. What draws them is the finish on it: sweat, body oils, food stains, and the residues of a season of wear. That is why holes cluster at collars, cuffs, and underarms — the zones that carried the most of you. Washing or dry cleaning before storage does double duty: it removes the attractant that would let a larva settle on an otherwise ignored sweater, and the process itself kills eggs and larvae already on the garment. Dry cleaning heat does it; a hot wash does it too, though most wool cannot take a hot wash, which is where the freezer comes in.

For pieces you cannot launder hot, sealed cold is the standard fallback: bag the garment, press out the air, and leave it in a freezer at -18 °C (0 °F) for at least a week, then thaw fully before the bag is opened. Cold at that temperature kills eggs as well as larvae, which matters because eggs are the part you cannot see. Do this before the garment enters storage, not after — the goal is a clean, empty container meeting a clean, empty sweater.

Seal the container, skip the shortcuts

What actually protects wool is a barrier the adult moth cannot get through to lay eggs. A rigid plastic bin with a tight lid, a zippered garment bag with no gaps, or a sealed archival box all qualify. What does not qualify: a lidded but vented basket, a suitcase with a worn zipper, and any fabric storage the moth can walk through. Moths seek out dark, still air, and an unsealed container in a closet is exactly that.

Vacuum bags seal well but press the fiber flat for months, which sets hard creases along fold lines and crushes the loft that makes wool warm. Fine for a season on sturdy knits; a poor trade for a good coat. Wherever the wool sits, keep it folded loosely with its natural shape respected, refolded along different lines from last year, and stored dry — damp storage brings its own problems, mildew chief among them.

Cedar and lavender: repellents, not killers

Cedar deserves its reputation and only that. The wood’s aromatic oils deter adult moths from settling, but the oils evaporate, a sealed cedar chest renews the effect far better than a block hung in open closet air, and the concentration anywhere in a home is nowhere near the level that kills eggs or larvae. Sanding a cedar block lightly re-releases the scent; a block left alone for years is furniture. Lavender behaves the same way — a deterrent with a shelf life, not a treatment. Pheromone traps sit in the same category from the other direction: they catch males, which makes them a useful alarm that tells you moths are present, and no defense at all for the wool itself.

The honest summary: repellents may reduce the odds of an egg being laid nearby, but only two things have done the real work — cleaning the garment and sealing it. Everything else is a pleasant smell in a room the moth has already decided about.

A fall routine and a spring inspection

The whole system compresses into one routine:

1. Wash or dry clean everything before it goes into storage.
2. Freeze what cannot be washed hot — sealed, a week at -18 °C, full thaw.
3. Store in a sealed bin or garment bag, folded loosely and kept dry.
4. Add cedar or lavender if you like the smell; count on it for nothing.
5. In spring, open every container and inspect before the wool goes back into rotation.

The inspection is where problems get caught early. Run a hand along seams, collars, and cuffs looking for sandy grit, silky webbing, and small irregular holes — and check the bin itself, since larvae wander. Finding one suspect garment in April is a freezer week; discovering the same damage in October means the whole container was compromised for six months. The same label-reading habits that predict how a knit ages — fiber, blend, and finish, as in reading a merino sweater label — apply here in reverse: cashmere and fine merino are the tenderest things in the drawer, which is why cashmere grade and price matter as much on the hanger as they do in the storage bin.