There are many myths out there in how to care for wool garments, and it is easy to get confused about which treatment is the best. For environmental reasons, some treatments are even contra dictionary to the purpose of using wool in the first place, like the use of dry cleaning. Here are some guidelines. They are collected from people who do research on wool, and from wool companies. The sources are found at the end. Air the garments! Since wool from nature does not allow for much growth of bacteria, it does not easily give away smell, and thus the first choice is to hang it out to air rather than put it to wash. Wool can be used several times before it is necessary to wash it. This holds for the base layers, the thin wool we use closest to the skin. For thicker hand knitted or commercially knitted sweaters, it would be enough to wash it once or twice a year, or when it looks dirty and smells. If put in storage during the warmer season, it should be clean. Dirty spots? If the garment has dirty spots, it is recommended to remove them, instead of washing the whole garment. When washing is necessary: Always read the washing label on the garment and follow the instructions. Machine wash: For base layer garments of thin wool, it is better to wash them in the machine than to hand wash. Some lamb, Cashmere, Alpaca, and Merino wool sweaters can be washed in the washing machine, but please always check the labels. The wool is already pre-shrunk. If you have wash bags, it may be a good idea to put the clothes in them, to protect them more. Turn the garments inside out. Use the wool program if the machine has it. If it does not have a wool program, a gentle action, and cold temperature is a good option. If you only have a few wool garments to wash, it is possible to wash them with other garments of similar colors as well, but with half a load rather than a full load. Always use a neutral, mild detergent, like Woolite, as other detergents may have enzymes or bleach that will deteriorate the wool fibers. It is not recommended to use a fabric softener, as with other detergents it may deteriorate the wool fibers. Base layer wool garments can hang to dry but should not be dripping wet. Gently squeeze the water out of the garments before hanging them. Tumble dry wool clothes? Wool clothes should in general not be tumbled. Why do we tumble dry any fabrics in the first place? I know, there are lots of reasons why we use the dryer. I have one. But fresh air drying is carbon free, and a really nice alternative. The clothes smell so much better when dried outside. Back to wool clothes – No, BUT: These days, there are Woolmark certified dryers out there. These are said to be safe, at least for the base layer wool. Wool clothes which are Woolmark certified are labelled ‘tumble dry’. So, they should be safe as well, even though the dryer doesn't have a specific wool drying program. Many of the base layer garments can be put in the dryer (as always, please read the label). For hand knit wool garments, I would not tumble dry my own, ever. Hand wash: The wool clothes are turned inside out. And, put in a tub/bucket, or in the sink with lukewarm water (86F/30C). Use 1-2 tablespoons with Woolite or another wool detergent. Move the garment carefully around in the tub/bucket, so that the detergent is mixed in. Wool should not soak over a long time (it can shrink). Carefully squeeze out the water with your hands. Rinse with water of the same temperature, and repeat until the detergent is gone, 1-3 times. Leave the garment to dry flat on a towel or on top of the drying rack, gently pull it to the desired form. If hung, it may lose its shape. Sources: https://us.daleofnorway.com/explore-dale/how-to-care-for-your-wool/ https://www.woolmark.com/care/ https://www.devold.com/en-gb/our-choices/wool-guide/how-to-make-wool-last/
