The first sign is usually small enough to ignore. A single hole in the front of a wool sweater, no bigger than a grain of rice, that you assume came from a zip or a stray nail. Then, a week later, a second one on the sleeve. Then a thin, almost bald patch near the collar of the coat hanging beside it. By the time most people say the word moth out loud, the problem has been quietly living in the closet for months.
For anyone who owns vintage wool, moths are the one threat worth taking seriously. Fading, pilling and stretched rib are slow and forgiving. Moth larvae can ruin a decades-old knit or a varsity jacket's body in a single season. The good news is that they are predictable, and a handful of simple habits keep them out of almost any wardrobe. This guide covers how they work, how to spot them early and how to store wool so they never get the chance.
01. Know the culprit
The moths that damage clothes are not the large, fluttering ones that circle a porch light. The two common household species are the webbing clothes moth and the case-bearing clothes moth. The adults are small, slender and pale buff or golden, often less than a centimetre long, and they prefer to scuttle or run rather than fly. If you see a tiny moth that flutters weakly away from light and into a dark corner, take note.
The adults do not eat your clothes. The damage comes from their larvae, small creamy-white caterpillars that hatch from eggs laid directly on fabric. Larvae feed on keratin, the protein in animal fibres. That makes wool their favourite, along with cashmere, mohair, alpaca, fur, felt, feathers and silk. Cotton and synthetics are rarely eaten on their own, but blends that contain wool are at risk, and larvae will chew through synthetic fibres to get at wool or at food and sweat stains.
That last point matters. Larvae are drawn to fabric that carries traces of sweat, skin oils, food and drink. A clean sweater is less inviting than one worn twice and put away. They also like the dark, quiet, undisturbed parts of a home: the back of a closet, the bottom of a storage bin, the underside of a rug, a box of knitting yarn in the basement.
02. Why vintage wool is especially vulnerable
Vintage wardrobes tend to have exactly what moths like. Older wool garments are often thicker and purer than modern blends: heavy knits, melton varsity bodies, wool shirts, toques, pennants and blankets. Many vintage pieces have also spent years in attics, basements and storage before they reach you, and those spaces are where moth populations build up quietly.
Vintage also tends to be worn less often. A heavy wool cardigan you bring out only in deep winter, or a team knit that lives in a drawer most of the year, is precisely the kind of undisturbed fabric that larvae thrive in. Regular wear, brushing and airing interrupt their life cycle. Long rests in the dark let it run.
And because each vintage piece is a one-off, damage is harder to accept. A modern sweater can be replaced. A sixties ski knit or a hand-knitted Cowichan cannot. That is reason enough to build some routines.
03. How to tell if you have moths
Early detection is worth more than any repellent. Make a habit of checking your wool every few weeks in the warmer months and every time you take something out of storage. Look for these signs:
- Small, irregular holes: often scattered rather than in one place, and frequently in hidden areas such as under the collar, at the armpits, along seams and where folds have sat untouched.
- Grazed patches: areas where the surface fibres have been eaten away, leaving a thin, slightly bald look before a full hole appears.
- Silken webbing or tubes: fine, dusty silk trails on the surface of fabric or in the creases, made by webbing clothes moth larvae.
- Small cases: tiny, flattened tubes the colour of the fabric, carried around by case-bearing larvae.
- Frass: tiny grains like coarse sand, usually the same colour as the fabric being eaten. You might find it in folds or at the bottom of a drawer.
- The larvae themselves: creamy, slightly translucent, with a darker head, often tucked into seams.
- Adult moths: small, pale, weak-flying moths in or near your closet, especially from spring through late summer.
Hold suspect garments up to a bright window. Thin spots that are not yet holes show clearly against the light. A soft clothes brush run over the surface will also lift eggs and young larvae into view, and brushing alone disrupts them.
Moths love what is forgotten. The best protection a wool garment can have is someone who keeps picking it up.
04. Prevention starts with clean clothes
The single most effective defence is never storing wool dirty. Even a garment that looks and smells fine after one wear carries enough sweat and skin oil to attract larvae. Before any wool piece goes into a drawer or a box for more than a couple of weeks, it should be clean.
For many wool garments, a gentle hand wash in cool water with a wool-safe detergent, followed by a careful press of the water out in a towel and drying flat, is enough. Some heavier garments, tailored coats and anything with leather or complex linings are better taken to a dry cleaner who handles older clothing. Either way, clean it before the season ends, not when you take it out again next year.
Between washes, brush wool garments after wearing with a soft clothes brush, working from top to bottom. Brushing removes surface dirt and food crumbs and dislodges any eggs that may have been laid. Air the garment for a few hours before putting it back. These small, regular actions do more than any spray.
Keep the space clean too. Vacuum closet floors, shelf corners and the edges of rugs regularly, paying attention to dark corners and gaps along baseboards. Empty the vacuum outdoors after cleaning an area you suspect.
05. Storage that keeps them out
Once wool is clean, the next job is to put a barrier between it and any moths in the house. Good storage choices include:
- Sealed plastic bins: with tight-fitting lids, for knitwear and folded wool. Add a layer of acid-free tissue between garments to reduce creasing.
- Zippered garment bags: breathable cotton bags are gentle on fabric but must be fully closed. Look for a bag with a zip rather than a drawstring.
- Resealable bags: for small items like toques, scarves, mitts and pennants, especially for long storage.
Moths cannot eat through a properly sealed container, but they can lay eggs on anything that goes into it. That is why cleaning first is essential: sealing a dirty or infested sweater in a bin just gives the larvae a private room.
Choose a cool, dry, dark spot for storage, but not a damp basement, which invites mildew. A closet shelf or under-bed space in a living area is usually better than an attic, which can get very hot in summer, or a basement, which can be humid.
06. Cedar, lavender and other deterrents
Cedar blocks, cedar hangers and cedar-lined chests are popular, and they can help, but it is worth being realistic. The aromatic oils in cedar may discourage adult moths and can affect young larvae, but the scent fades over time, and cedar alone will not stop an established infestation. If you use it, lightly sand blocks every season to refresh the scent, and treat it as one layer of protection rather than the whole plan.
Lavender sachets, cloves and other herbal deterrents are similar. They may make a closet less appealing to adults and they smell lovely, but they are not a reliable cure. Use them alongside cleaning and sealed storage, not instead of them.
Pheromone traps are useful for a different reason. They lure male moths onto a sticky card, which tells you whether you have moths and roughly how many. They are a monitoring tool. They will not protect clothing by themselves, but a trap that keeps catching moths is a clear sign to inspect everything.
Traditional mothballs work but come with real drawbacks. They release strong chemical fumes that cling to clothing and can be harmful to people and pets. Many collectors and conservators avoid them for that reason. If you choose to use any chemical treatment, follow the manufacturer's instructions closely and keep it well away from living spaces.
07. Dealing with an infestation
If you find evidence of moths, act methodically. First, take everything out of the affected closet or drawer. Separate wool and other animal-fibre items from cottons and synthetics. Inspect each piece in good light, brush it thoroughly outdoors if you can, and set aside anything with signs of activity.
Then treat the garments. Washing in warm water with a wool-safe detergent will kill many eggs and larvae, though high heat risks shrinking or felting wool. Dry cleaning is also effective. For pieces that cannot be washed, freezing is a common approach: seal the garment in a plastic bag, pressing out as much air as possible, and leave it in a household freezer for at least several days. Many people prefer a full week, and some repeat the process after thawing to catch anything that survived. Let the bag come back to room temperature before opening it, so condensation forms on the outside of the plastic rather than on the fabric.
While the clothes are out, clean the space thoroughly. Vacuum every surface, corner and crack, wipe shelves and drawers, and wash the closet floor. Check nearby rugs, upholstered furniture and any stored wool such as blankets or yarn, because moths do not stay politely in one closet.
For a large or persistent problem, a professional pest-control service may be worth calling. Keep pheromone traps in place for several months afterwards to confirm the population is gone.
08. Quarantine every new arrival
Vintage collectors have one extra job: making sure new pieces do not bring moths with them. Any wool, fur or silk garment you buy second-hand should be inspected before it joins the rest of your wardrobe. Look it over carefully in daylight, brush it, and check the seams, collar and cuffs.
If you have any doubt, clean it or freeze it before hanging it in your closet. It is a small delay, and it is far easier than treating a whole wardrobe later. Even a garment from a careful shop or a trusted friend has had a life before you, and a short quarantine is simply good practice. At Throwback Vault, as at any vintage store, wool pieces arrive from many different homes, so build the habit for everything you bring in.
09. A simple routine for the year
None of this needs to be complicated. A seasonal routine covers most of it:
- In spring, clean every wool garment you are putting away, brush it, and store it sealed with cedar or lavender if you like.
- Through the warm months, set a pheromone trap near your storage and check it every few weeks.
- In early fall, take everything out, inspect it in good light, air it and brush it before wearing.
- All year, brush wool after wearing, vacuum the closet regularly, and quarantine anything new.
Do that, and moths become a minor nuisance rather than a disaster. Your vintage wool, whether a heavy knit, a varsity jacket or a soft old toque, will keep doing what it was made to do: keep someone warm through a long Canadian winter, for another decade or two at least.
