Socks are knitted garments made to enclose the foot, usually extending up the lower leg. They serve several purposes: easing the chafing that footwear causes against bare skin, keeping the feet warm, and absorbing perspiration.
That last function is where the choice of fibre matters most, and it is where wool is genuinely different.
Moisture
Feet produce a surprising amount of moisture over a day. What a sock does with it determines almost everything else.
Cotton absorbs moisture and holds it. A damp cotton sock stays damp, which is why cotton socks feel cold and clammy after a few hours and why they cause blisters on long walks.
Synthetics wick moisture away but do not absorb it, so it has to evaporate from the surface.
Wool absorbs a great deal of moisture and still feels dry. It can hold roughly a third of its weight in water before it feels wet to the touch, and it keeps insulating while damp. That combination is why wool socks are the standard for walking and cold weather.
Warmth
Wool’s crimped fibres trap air, which is what does the insulating. It works when damp, which cotton does not – a wet cotton sock is actively cold.
It also regulates in both directions. Fine merino socks are comfortable in summer, which surprises people who think of wool as a winter-only fibre.
Odour
Wool resists odour considerably better than synthetics. The fibre structure is less hospitable to the bacteria that cause it, so wool socks can be worn longer between washes without becoming unpleasant.
This is why walkers carry fewer pairs of wool socks than they would of synthetic ones.
Durability
Here wool needs help. Pure wool wears through at the heel and toe quickly.
Sock yarn almost always contains nylon – usually around twenty per cent – and that is what makes the socks last. If you are knitting socks, do not substitute a pure wool yarn and expect them to survive.
Comfort
Wool has natural elasticity, so socks keep their shape and stay up rather than sagging around the ankle. Cotton has none, which is why cotton socks bag.
If wool itches
Most people who believe they cannot wear wool have only worn coarse wool. Merino and other fine wools are a different experience entirely, and the micron count matters more than the fibre.
Superwash merino sock yarn is soft, machine washable and readily available.
Care
Machine wash superwash sock yarn cool and dry flat or on low. Untreated wool needs hand washing and will felt in a hot wash.
