Washing wool sweaters

Washing sweaters (particularly wool sweaters) is a simple process, but one fraught with pitfalls for beginners, as you can easily tell in any trip to a thrift store, where many very small and very fulled sweaters await a better home. Much mythology has accumulated around this, and none of it helps, while some of it is downright counterproductive. To add insult to injury, many of the current crop of Moms, normally the dispensers of good advice, grew up in the era of polyester and acrilyc, not to mention under the rule of the washing machine. They're just as shaky about wool as the offsprings who're now taking up knitting.

So first let's get a couple things clear. The main idea is to get the thing clean. This generally involves water :-), and it also tends to involve some sort of soap. When you're dealing with wool, the main pitfall is fulling. So we recommend you start by reading our article on fulling so you know what the process is about, and what not to do. The other pitfall in most sweaters is stretching under the weight of water, and that's easily avoided.


The most efficient way to wash sweaters is in hot water. That's right, the Moms are blanching right now. But hot water will help any grease dissolve (including human skin oils rubbed in around the neck), it'll get rid of that dust and grime efficiently, it'll kill some of the accumulated beasties, wash off that pet dander and antique lunch sample, the works. Don't be afraid of it. The hotter the better, within reason.

What causes fulling is abrasion, not heat. Which means you must handle your sweater very gently while it's wet, in fact it's better not to handle it at all. Laying it on the soapy water like a baby is all you want to do, without any wringing and scrubbing, even without any idle swishing. That's all there is to it.

Soapy matters

Choice of soap is important, as you can greatly facilitate fulling with the wrong choice. Basically, soap is out. Alkaline pH helps open up the little wool scales, and you're just asking for help in fulling. Soap is by definition alkaline, so it's best avoided, reserved for your deliberate fulling projects. Rubbing a bar of soap on a spot can do untold, permanent damage. If you have a horrible set-in stain, take it to a dry cleaner - they're trained to deal with it, and they have access to chemicals you wouldn't believe.

There is also much mythological agitation around Woolite, but it's just a publicity scam. Woolite was 'gentle' in the 50s, if you compared it to the usual regime of hot water and Tide in the machine, with bleach to boot. It was gentle mostly in that it firmly recommended hand washing. But it's not a gentle product, it's very alkaline and strips the hell out of innocent wool fibers. Leave it to the uninitiated.

What you really want to use is detergent. The best is Dawn dishwashing liquid. Nice pH, very similar composition to the much more expensive synthrapol that you buy in reputable dye stores. It's both very effective and very gentle. It's what they use to wash birds caught in oil slicks, so that tells you that it can get rid of a bad mess, but also that the fragile feathers are not stripped to uselessness after treatment. Now the weird part is that the flavor/color of Dawn matters some :-). The original blue is the best in terms of avoiding fulling, it really keeps those little scales closed. The much-lamented yellow (now unavailable) was a dead ringer for synthrapol, so your colors would never run. Who knows about the other flavors. But on the whole, if you can find blue, use it, especially if it's 'original fragrance'. The concentrated version is OK as far as I can see, you just need to use less of it, and I've also had good luck with the 'fast acting' version, which does act faster but doesn't seem to act significantly different.

In a pinch, other detergents will do. Dish detergents are a good place to look, as long as you take a good look at the label and make sure it's detergent and not soap. I've used groovy German Ecover without harm. Regular laundry detergent usually is not strong enough on the grease, and geared mostly to cotton. In a pinch, shampoo will also do nicely, as long as it's mild shampoo without conditioner. Wool is hair after all (and silk is similar enough), so washing it with stuff that's good for your hair is not a problem, you've presumably tested that thoroughly. The thing though is that shampoo is often riddled with extra thickeners, perfumes and colors that are present to a much lesser degree in dish detergent. And some people advocate conditioner for wool as a rinse, but that's another fallacy. Conditioner tends to be too alkaline for wool to be happy in the long term, and to be full of extraneous ingredients that'll only attract dirt to your sweater faster. It's never going to make rough wool feel softer. If you don't wreck your sweater with bad soap, there's no need for conditioner.

Washing by hand

So the process itself is very simple, at least very low-labor. Run hot water into a basin/bathtub/sink. Just hot water, nothing else - hot water pouring energetically onto a sweater can generate enough turbulence to full a spot right there. When you're done, add a squirt of detergent. The same kind of squirt you'd use for dirty dishes, nothing more is needed. You're allowed one quick swish there, to mix it with the water, but not enough to foam it, and before you touch any wool. Then lay your sweater down on the water, and do nothing else. Maybe gently lay your hand and weigh it down so it gets wet faster, but really that's not necessary. Go away, resisting the urge to swish anything, much less rub, wring and mutilate. Swishing is abrasion! The water and detergent will get to every apparently neglected part and do their work without any help, given time and patience.

After a suitable amount of time (15-20mn? overnight?), come back and gently pour out the water, and transfer the sweater to another container, supporting its weight as you go so it doesn't get any fatal stretching, wool is more fragile when wet. Pour clean hot water into the basin/whatever. Lay the sweater back down on the water. Wait again, the soap will disperse on its own. I generally do 2 rinses for good measure, I like to see clean water before I'm through, but that's up to you. Also, if your water is very harsh and alkaline, a small glug of vinegar in the last rinse may be a good idea, just like your grandmother used to do for her hair.

When you're done rinsing, let the sweater drain a bit. A colander is fine, wool is hardly poisonous, especially if its only possible contaminant is dish detergent. Then lay it gently on a towel, roll the towel, and press it. Don't wring it, rub it, abuse it in any way, just press. You can stand on it if it's a big towel and a large sweater, as long as you're only using pressure and not rubbing in any direction whatsoever. The sweater should merely be damp after this, not wet, or you can repeat if you have more towels handy.

Machine help

If you wish to use a washing machine, you'll need one of the top-loading, water-guzzling, SUV kind of models with a control panel accessible. A laundromat rarely provides that kind of fine control, you usually get stiffed for every filling and can't get directly to the spinning cycle.

Fill the machine, then add detergent (1/4 cup of Dawn). You don't want the detergent in right off, or foam will spew out like a horror movie. It's helpful if you're able then to move the dial to 'spin' after the machine is full of water, before you do anything with wool. This will prevent any spastic accidents, the top falling and allowing agitation to start. Kiddies and kitties have been known to cause this to happen as well, even if you're not usually as much of a klutz as I am. And even a few quick 'whoosh whoosh' can full a vulnerable item.

Then lay the sweater on top of the water and let it soak. Take the sweater out, then spin the water out, repeat the process to rinse. The big advantage of a machine, and one that you can do even if otherwise hand-washing, is putting the wet sweater in the empty machine and putting it through a spin cycle, this will get it to barely damp condition without abrasion, although possibly with a bit of stretching. Volume is also more of an option, you can wash several sweaters together (although you might want to think about how many you can dry at once before you get carried away).


You're done with the heavy labor. Lay your sweater down on a clean dry towel on the floor, arranging it artistically so it doesn't look any different than it did before, ie so it's not distorted in one direction or another. Or better yet lay it on one of those sweater racks with netting, so it dries faster, but that's strictly gravy. The idea is that wet wool will stretch, and that it'll set in that position if you allow it to dry that way. What you'll hear about as "blocking" is nothing more than that, except that you're trying to distort the sweater on purpose to suit yourself. I try very hard to stay away from that necessity, by working harder on the original fit ;-). But in any case, you want to put your sweater in an agreable position while it's wet, and let it set that way. We're still wet enough to full here, so you don't want to be brutal at shaping, think of it as influencing the shape more than anything.

Try to keep the sweater away from kitties, who love clean sweaters, particularly when they're padding a little kitty-size hammock. Every 12 hours or so, test it, flip it, refold the sleeves in another direction, in short expose the still-damp parts to air. Drying time can be 12-72 hours, depending on your climate, how thick the sweater, and how damp it was to begin with.

That's it

Keep in mind that the process of fulling can pick up again at any time. Just because your wool sweater has looked the same for years doesn't mean it can't be ruined by an unfortunate round of machine washing, or a little roughness in the sink. Wash it this way consistently and it'll outlast you.

First published: 11/16/02

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