Sweater season is officially upon us, but with the coziness comes a pesky concern: do you have moths? Are they laying eggs on your cashmere sweater right this minute, promising to chew tiny but irreparable holes into your clothing?
Maybe, but before we get into what to do about it — because there are things to do that don’t include odorous mothballs — it helps to know what moths are doing in your closet in the first place. “There are two different types of moths that damage textiles: webbing and case-bearing clothes moths,” says Meredith Wilcox-Levine, a professional textile conservator at Textile Conservation Workshop. Both kinds of moths eat textiles, but the latter does something called grazing, chewing at a top layer of fabric without leaving a hole. They also are both more of a nuisance in larval form, rather than in winged form. Wilcox-Levine describes them as “tiny, nearly transparent caterpillars,” explaining that they eat protein to prepare for metamorphosis. Unfortunately, “at the point where larvae are large enough to be easily noticeable, they will already have eaten away at your favorite items [in order] to reach that size,” says Corinna Williams, co-founder of the Brooklyn laundromat-slash-coffee shop Celsious. If anything, looking for the cocoons can at least confirm that it’s moths, and not wear-and-tear, causing the holes.
That makes dealing with the problem a matter of prevention and eradication. We asked four experts — Gwen Whiting and Lindsey Boyd, co-founders of laundry products brand The Laundress, Wilcox-Levine, and Williams — about how to deter moths, and how to evict them (and prevent them from reproducing) if they’ve already taken up residence.
How to prevent moths
To prevent a moth infestation, Whiting says you should first learn what they like to eat, and what they can’t eat. “Moth larvae typically target clothes made from animal fibers such as silk, wool, cashmere, angora, or fur, and materials that contain keratin, the fibrous structural proteins found in our skin and hair,” she says. There’s one useful exception: “Moths cannot eat through cotton,” Boyd says. For that reason, she and Whiting recommend storing vulnerable clothes in breathable cotton canvas bags with zipper closures, and to avoid plastic or cardboard that could trap moisture and create moth-friendly humid environments.
This zip-up box is sweater-shaped.
For longer garments that get stored under the bed or in drawers.
Whiting advises against using mothballs, which she says are “are toxic and leave permanent, noxious odors.” (Plus, we all know they smell awful.) She also warns against cedar wood blocks or chips, which can leave stubborn oil stains on fabrics or cause acidification damage. Instead, she recommends lavender pouches that can attach to hangers or get tossed into drawers. “Lavender has been used for centuries for its bug-repelling properties,” she says. “It has terpene compounds that are said to help keep moths away,” she says. As for what terpene compounds are: the linalool, linalyl acetate, cineole, and camphor in lavender are what’s thought to help repel moths, as well as other pesky insects like mosquitoes. The latter two compounds are thought to have insecticidal properties. Those are also found in rosemary, but at lower levels than in lavender, which is why we’re talking about lavender (and not rosemary).
Lavender oil is a good idea for scaring off clothes moths, too. Williams suggests hand-washing “vulnerable garments” with a few drops of natural essential lavender oil at the end of the season. The oil can also re-scent pouches that have faded over time.
“If you want to add an extra layer of security, place one pheromone trap in your closet to attract male adult moths and prevent them from procreating,” Williams says. Pheromone traps are non-toxic, sticky traps that lure and kill adult moths with the artificial scent of a mate. “This type of trap is the way to go, rather than a cheaper, sticky ‘catch-all’ trap,” says Wilcox-Levine. And you only need one: “Moths can detect the pheromone from hundreds of feet away, so placing more than one can actually confuse them and just make them flutter back and forth,” Williams says.
To top that off, you can always try fighting the moths with extreme temperatures: Williams then suggests ironing out dry items, because the heat can kill any larvae still clinging on to fibers. Conversely, anything that can’t be ironed can be frozen: “Place infested items in disposable, airtight bags to store them in the freezer for a few days,” suggests Boyd. In order to truly kill moths of all ages, specifically the cocoon-protected larvae, Wilcox-Levine says you’ll need something colder than the chill levels of a home freezer. Instead, you’ll need to put moth-infested items in a sub-4 degrees freezer, for a period of at least two weeks.
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