Wash a wool or cashmere sweater by hand, in cool water, with a pH-neutral wool detergent. Soak it for ten minutes without agitating, rinse in water of the same temperature, press the water out rather than wringing, roll it in a towel, then dry it flat and reshaped. Never hang knitwear, never use hot water, and never use a detergent containing enzymes. Do that and a good sweater lasts a decade.
Almost every ruined sweater is ruined the same way: heat plus agitation. Wool fibers are covered in microscopic scales. Warm them, wet them and move them against each other, and the scales interlock permanently. That is felting — the garment comes out smaller, denser and stiffer, and nothing brings it back. Everything below follows from avoiding that one reaction. The knitwear it applies to is in the BEARING catalog.
How often should you wash a wool sweater?
Far less often than you think — every three to five wears for most men, or whenever it is visibly soiled or has picked up an odor it will not shed. Wool is naturally odor-resistant and self-refreshing. Airing a sweater overnight does most of what a wash would do, without the wear.
Between wears, lay the garment over a chair back in open air, then fold it away. Give it a day off before wearing it again; the fiber needs time to recover its elasticity, and rotation is the cheapest way to extend the life of knitwear. Cashmere benefits most — its fibers have less natural spring than sheep's wool and stretch out faster under consecutive wear.
How to hand wash a wool or cashmere sweater
- Read the care label first. If it says dry clean only, treat that as the maker's instruction. Everything else here assumes a washable knit.
- Fill a clean basin with cool water. Around 68°F / 20°C, and never above 86°F / 30°C. Cold to lukewarm — never warm to the touch.
- Add a wool-specific or pH-neutral detergent. A capful is enough. Swirl it through the water before the garment goes in.
- Turn the garment inside out and submerge it. Press it under gently. Do not rub, twist or scrub.
- Soak for five to ten minutes. Longer does not clean better and risks color bleeding.
- Rinse in water at the same temperature. A temperature change between wash and rinse is itself a shock to the fiber. Repeat until the water runs clear.
- Press the water out. Support the whole garment, squeeze gently, and never wring. Wet wool is heavy and stretches under its own weight.
- Roll it in a dry towel. Lay the sweater flat on a towel, roll the two together, press along the roll to draw out moisture.
- Dry flat, reshaped, away from heat. On a fresh towel or a mesh rack. Pat the body, sleeves and collar back to their original dimensions while damp. No radiator, no direct sun, no dryer.
Which detergent should you use on wool and cashmere?
Use a detergent made for wool, or any pH-neutral liquid without enzymes. Wool and cashmere are protein fibers, and the protease enzymes in most biological and stain-fighting detergents are designed to break protein down. They will slowly digest the garment.
- Avoid: biological or enzyme detergents, chlorine and oxygen bleach, and anything alkaline.
- Avoid: fabric softener. It coats the fiber and flattens the loft that makes the knit warm.
- Use sparingly: detergent generally. Excess is hard to rinse out and leaves the hand stiff.
Can you machine wash wool?
Sometimes, and only on a dedicated wool or hand-wash cycle with cold water and the lowest spin the machine offers. Those cycles are designed to hold the garment still in water rather than agitate it. Put the sweater in a mesh laundry bag, turned inside out, and wash it alone or with similar items.
Cashmere is a different matter. Hand washing is the safer default — the fiber is finer, shorter and less elastic, with less margin for a machine getting the cycle slightly wrong. If the care label permits machine washing, follow it exactly. If it does not, do not experiment.
How do you deal with pilling?
Pilling is normal, not a fault. It happens where fiber ends work loose under friction — underarms, sides, cuffs and anywhere a bag strap sits. Remove pills with a sweater comb, a knit stone or a battery shaver, working in one direction with the garment laid flat and unstretched.
Never pull pills off by hand — that drags fiber out of the yarn and thins the knit. Pilling is heaviest in a garment's first few weeks and slows once the loose surface fibers are gone, so de-pill early and the problem largely resolves itself.
How do you store wool and cashmere for the summer?
Clean it first, fold it, and store it somewhere dry and breathable. Clothes moths do not eat clean fiber by preference — it is the larvae that feed, and they are drawn to garments carrying body oils, perspiration and food traces. An unwashed sweater put away in April is an invitation.
- Fold, never hang. A hanger loads the weight of a knit onto two shoulder points and distorts them permanently.
- Use breathable storage. Cotton bags or boxes. Airtight plastic traps moisture against the fiber and can cause mildew.
- Keep it dark, dry and cool. Not a damp basement, not a warm attic.
- Cedar and lavender deter, they do not kill. Both are worth using; neither replaces cleaning the garment first.
- Freezing kills larvae and eggs. Seal a suspect garment in a bag and freeze it for around 72 hours.
Do wool and cashmere need dry cleaning?
Rarely. Structured garments — a tailored coat, a wool trouser with a lining — should go to a dry cleaner, because they cannot be reshaped flat after washing. Unstructured knitwear generally does better with a careful hand wash than with solvent.
Dry cleaning is not harmful in itself, but repeated cycles strip natural oils from the fiber and leave it drier and less resilient. Use it once or twice a season for the pieces that need it, and hand wash the rest. A tailored trouser such as the Kensington Trouser ($74.99) in herringbone wool-blend falls on the dry-clean side of that line; check the Materials & Care panel on the product page for the specific instruction.
Fixing common problems
| Problem | Cause | What to do |
|---|---|---|
| Sweater has shrunk and stiffened | Felting — heat and agitation locked the fiber scales together | Not reversible. A cool soak with hair conditioner and gentle stretching while damp may recover a little size, but the hand feel does not return |
| Cuffs and hem have gone slack | Stretched fiber, usually from consecutive wears or hanging | Wash cool, then dry flat with the ribbing pushed back into shape. Rest the garment between wears afterwards |
| Shoulders have grown points | Stored on a hanger | Wash and dry flat to release. Fold from then on |
| A pulled thread or snag | Caught on a watch, a zip or a fastening | Never cut it. Use a needle to draw the loop through to the inside of the garment, then ease the surrounding stitches flat |
| Small hole in a fold line | Usually moth larvae rather than wear | Freeze the garment, clean it, then have it rewoven or darned. Check everything stored nearby |
| Creased after storage | Compression in folding | Steam it, or hang it in a bathroom during a hot shower. Avoid direct ironing |
| Fresh stain | Spill | Blot, never rub. Cool water and a little wool detergent, worked from the outside of the mark inward |
Can you iron wool and cashmere?
Steam rather than iron wherever possible. Wool relaxes readily in steam, and a handheld steamer or ten minutes in a steamy bathroom removes most creasing without the fiber touching anything hot.
If you must iron, use the lowest wool setting, turn the garment inside out, and always place a pressing cloth between the iron and the knit. Direct contact flattens the surface and can glaze the fiber, leaving a permanent shine.
A short seasonal routine
- Every wear: air the garment before folding it away. Rotate rather than repeating.
- Every three to five wears: hand wash cool, dry flat.
- Monthly in season: de-pill the friction points.
- End of season: wash everything, dry it fully, fold it into breathable storage with cedar or lavender.
- Start of season: unpack, air for a day, steam out fold creases before the first wear.
Care is not a chore attached to good clothing — it is part of the argument for buying it. A garment you maintain gets better with time; one you replace every year never does. That principle runs through how BEARING is built, and through old money style and the warm-weather equivalent of this guide in our linen guide. Choosing between fibers before you buy is covered in linen vs cotton.
Frequently asked questions
Can you put a cashmere sweater in the dryer?
No. Heat and tumbling together are the exact conditions that felt wool fibers. Dry flat, away from direct heat and sunlight, reshaping the garment while it is still damp.
What temperature should you wash wool at?
Cool — around 68°F / 20°C, and never above 86°F / 30°C. Keep the rinse water at the same temperature as the wash water, because a sudden change is itself enough to shock the fiber.
How do you get the smell out of a wool sweater without washing it?
Air it. Hang it in a well-ventilated room, or outside in shade on a dry day, for a few hours. Wool sheds odor on its own, which is why it needs washing far less often than cotton.