Did you know that ‘superwash’ wool has been coated with plastic – or had the cusps/hooks/ of the wool chemically removed?
I knit a lot with ‘superwash’ for the simple fact that I like fingering (sock or 4 ply) weight yarns which seem to be mostly available ‘superwashed’. This weight makes a garment that is in best proportion to my short body. It comes in so many gorgeous, hand-dyed, vibrant colours. I like vibrant, too. As I realise the damage to the environment all plastics are making, I’m having to rethink my purchasing choices.
Because, the cusps have been flattened (with the plastic coating, or removed with the chemical treatment) the fibres pill less, BUT they also have lost some of the ability to bounce back. The garment can get out of shape as a result. There are ways to overcome this, one of which is to use a stitch pattern with lots of changes from knit to purl as each change will help grab the yarn. This technique works for acrylic yarns, too. I once knit a 100% acrylic in which every knit stitch was knit through the back of the stitch, which also controls stretch. No stretch, but also no drape.
Look for yarns that have not been chemically treated if you want to reduce your damage to the environment. These yarns tend to be longer wearing, too.
For more about Superwashed wool you might like to read this article
There is a lot of snobbery about yarn choice. Yes, I, too, love a soft luxurious yarn, but for a longer-lasting garment you might be better off with a natural ‘un-superwashed’ yarn like KnitPicks Palette and Wool of the Andes. Both are economical, too. With gentle, mindful washing, and drying flat, a garment knit in a natural wool will last, and look good, for several life times. Also in this category is the American made Brooklyn Tweed Loft which is getting a lot of notice at present.
And for longevity (with careful washing) there is nothing quite so good as a yarn with mohair in it. Mohair is both super soft (kid mohair is softer than yarn made from an older animal so look for “Kid Mohair” if you find mohair scratches you) and super strong. If you want to make long lasting socks and want to protect the environment, avoid the wool & nylon mixes and go for the wool & mohair instead.
For a super soft yarn that is also helping the environment I recommend one that contains up to 30% possum fur. The Australian Common Ringtail Possums were introduced to New Zealand to start a fur trade but they are now #1 nuisance as, in New Zealand, they have no natural predators and pray on the ground-living birds. New Zealand is trying to cull the explosion of possums and when you buy a yarn with possum in it you are helping control that pest.