Clothes moths: why storing away your summer wardrobe in October triggers winter's infestation

The scenario unfolds with mechanical regularity. In late September, you fold up the linen dresses, the T-shirts and the lightweight shirts, cram them into a garment bag or an under-bed box, and bring the jumpers, coats and throws up from the cellar. Six weeks later, in mid-November, you pull on a merino wool cardigan and discover three round holes on the shoulder, clean-edged, with no fraying — the signature of a clothes moth larva.

In between, nothing visible happened. That is precisely the problem: the clothes moth works in darkness, in stillness and in warmth. And autumn, with the heating coming back on and wardrobes that won't be opened again for weeks, offers exactly what it is looking for.

This article sets out the insect's real life cycle, the signs that are routinely mistaken for ordinary wear, and the treatment protocol that actually works — without turning your bedroom into a gas chamber.

Man in an orange coverall holding two blue rubbish bags, next to an orange sprayer

The moth you squash against the wall doesn't eat a thing. The adult Tineola bisselliella has atrophied mouthparts: it does not feed. The damage is caused exclusively by the larvae, which live hidden in folds, hems and pockets. Killing the adult moths therefore never resolves an infestation: it only reduces future breeding.

Clothes moth or pantry moth: don't fight the wrong battle

The confusion is common and costs weeks. The two families share neither diet, nor hiding places, nor treatment.

One simple rule: if the affected textile is of animal origin, it's a clothes moth. Pure cotton and polyester are never attacked as such — but a cotton T-shirt stained with sweat, milk or sauce may well be, because the larva consumes the organic residues.

The life cycle: four to six months of appetite, two weeks on the wing

Understand the calendar and you understand why you never see it coming.

In a home heated to 20–22 °C there are therefore 2 to 4 generations a year, rather than the single one seen in an unheated house a century ago. Central heating has turned the clothes moth into a year-round pest, with damage peaking in winter on stored garments.

That is also why a textile put away "looking clean" in late September can come back out riddled with holes in February: the eggs were already there when it was stored.

Eight signs mistaken for ordinary wear

1. Round or oval holes, 2 to 5 mm, with clean edges, often clustered — wear, by contrast, thins the knit gradually.
2. Worn patches on shoulders, collars and underarms: the larva attacks sweat-impregnated fibres first.
3. Small silky cases the same colour as the fabric, stuck in a fold, sometimes mistaken for lint.
4. Fine sand of droppings, the colour of the textile consumed, at the bottom of the drawer or garment bag.
5. Beige moths that hop along the floor when you pull out a box, rather than flying towards the lamp.
6. Wispy webbing under a wool rug, in the area covered by a piece of furniture that is never moved.
7. Piano felt, chair glides, rug underlay fraying for no mechanical reason.
8. Coat lining worn bare on the inside while the outside looks intact.

Cast-iron storm drain grate set in a pavement's concrete, blocked by green leaves

Why October is the pivotal month

Three phenomena overlap at the same time of year, and it is that overlap which triggers the winter infestation.

• Packing away the summer clothes. Garments worn and then folded away without a proper wash carry traces of sweat and sebum: a chemical signal that attracts egg-laying. A closed, dark, undisturbed garment bag becomes an ideal incubator.
• Bringing out the stored woollens. Coats, throws and wool duvets come up from the cellar or garage, sometimes already carrying eggs picked up over the summer. They are then hung in a healthy wardrobe, which they contaminate.
• Turning the heating back on. Going from 16 °C to 21 °C in a bedroom markedly accelerates larval development. What would have taken six months now takes three.

To this can be added a fourth factor, specific to 2026: the rise of second-hand clothing. Pre-owned wardrobes, clothes swaps, flea markets and end-of-season vintage shops circulate old woollen textiles that have never been treated. The risk is not theoretical: a single coat carrying a few eggs is enough to seed an entire wardrobe.

The treatment protocol that really works

The aim is simple: kill every stage (egg, larva, pupa, adult) and remove the refuges. Set aside a full day for it, not half an hour.

1. Empty everything out

Take everything out of the wardrobe, drawers and boxes included. Partial treatment fails every time: the larvae simply migrate to the untreated area. Sort on the floor, in good light, item by item.

2. Treat each textile with heat or cold

Both methods are proven and free, provided you respect the thresholds.

With freezing, it is the sharp drop in temperature that kills: don't open the bag until it has returned fully to room temperature, or you'll get condensation. Extra-large zip-lock freezer bags make the job far easier than a stack of boxes.

An upright garment steamer is also genuinely useful on structured garments that can go neither in the machine nor in the freezer: a slow pass in contact with the fabric, particularly in hems and under collars, destroys eggs and larvae without soaking the item.

3. Sanitise the furniture and the room

• Vacuum thoroughly: drawer bases, grooves, hinges, dowel holes, skirting boards, under heavy furniture, carpet edges. A vacuum with a HEPA filter avoids scattering eggs and scales back into the room.
• Dispose of the vacuum bag immediately inside a sealed bag, outside the home.
• Wash the surfaces with hot soapy water, then dry.
• Move the furniture: under a sideboard or a bed that has never been shifted, there is almost always a residual population in the carpet or the dust.

4. Monitor with pheromone traps

They don't treat, but they measure. Pheromone traps for clothes moths capture the males and let you tell, week by week, whether the population is collapsing or picking up again. Beware: pantry moth models do not work on Tineola bisselliella, as the pheromone is different. Place one in each vulnerable room, note the date and count the catches every fortnight. Zero catches over six weeks = infestation under control.

5. Put everything back properly

Return only treated textiles, to a dry, cleaned piece of furniture. Valuable items (cashmere, coats, suits) are best stored in vacuum storage bags or closed cotton garment bags — never in thin, punctured plastic, which lets the females through.

Rusty cast-iron manhole cover set into the concrete of a street, surrounded by green moss

What doesn't work (or barely does)

• Mothballs. Naphthalene has been banned from sale to the general public in the European Union since 2008 because of its toxicity. If you come across some in an inheritance, don't use them: air the room and take them to a waste disposal centre.
• A simple lavender or cedar sachet. Their effect is repellent and partial, never lethal. They have no action whatsoever on eggs already laid. Useful for upkeep after treatment, useless as a treatment.
• Single-use "shock" aerosol bombs. They kill the visible adults, not the larvae protected in folds and cases. ANSES, which handles the registration of biocidal products in France, regularly points out that such products dispense with none of the mechanical measures (washing, vacuuming, removing harbourage).
• Ultrasonic devices. No proven effectiveness against insects in real-world conditions.
• A 30 °C machine wash. The lethal threshold for the eggs is not reached. A gentle wash cleans; it does not disinfest.

A seasonal warning. French health authorities issued repeated alerts in 2026 about the circulation of banned insecticide products, sold online or hand to hand, to deal with bed bugs — with serious poisonings as a result. The same instinct applies to moths: only buy products carrying a legible marketing authorisation number, and read the label. With textiles, mechanical methods (heat, cold, vacuuming) outperform chemistry anyway.

Prevention: five habits that are enough

1. Never put away a garment that has been worn. That's rule number one. Sweat, sebum, food residues: these are what attract egg-laying, far more than the fibre itself.
2. Rotate your wardrobe. A wardrobe that is opened, disturbed and lit regularly makes a poor habitat. The items never touched are the first to be attacked.
3. Isolate long-term storage. Out-of-season clothes go into airtight containers, clean and dry. Rigid plastic airtight storage boxes are better than a cardboard box, which is porous and attractive to moths.
4. Quarantine second-hand items. Every pre-owned garment in wool, silk or fur goes through a 60 °C wash, the tumble dryer or the freezer before entering the wardrobe. The same goes for an antique rug or an armchair covered in felt.
5. Vacuum the dead zones once a month. Under beds, behind chests of drawers, along carpet edges, under wool rugs. That's where the residual pockets nobody sees take hold.

For valuable items, breathable cotton moth-proof garment bags, combined with red cedar blocks sanded once a year, make for sensible upkeep — provided the wardrobe has been sanitised beforehand.

Wet cast-iron manhole cover set into the dark asphalt of a street

When to call in a professional

DIY treatment is enough in the vast majority of domestic cases. It reaches its limits when:

• the infestation affects a wool carpet or antique rugs over large areas;
• the damage involves upholstered furniture, horsehair, piano felt or museum textiles;
• it concerns a hotel, holiday let, clothing shop, vintage store or dry cleaner's, where the turnover of textiles constantly re-seeds the premises;
• pheromone trap catches fail to drop after two full treatments, a sign of an unidentified harbourage (loft, insulation, bird's nest under a roof, an old rug rolled up in a cellar).

A pest control professional always starts with an inspection: without locating the source, no treatment holds. Depending on the situation, they will combine an approved surface treatment, steam treatment and, for structural harbourage, work on cavities and insulation.

The essentials in five lines

• The larvae are what eat, not the moths: killing the adults is never enough.
• Heat (60 °C / tumble dryer) and cold (−18 °C, 72 h) kill every stage, free of charge.
• Vacuuming + immediate disposal of the bag is worth as much as any product.
• Pheromone traps are for measuring, not treating.
• Storing a garment clean, dry and in an airtight container does 80% of the preventive work.

In October the window of opportunity is ideal: you are handling your entire wardrobe anyway. You may as well let that annual ritual serve as a fresh, healthy start rather than sealing in an infestation for the whole winter.

Sources and references: ANSES (biocidal products and pest control), INRS (naphthalene toxicological data sheets), European REACH regulation on the restriction of naphthalene, entomological literature on Tineola bisselliella.