How to Wash Merino Wool
Machine wash cold on a gentle cycle. Lay flat to dry. Then mostly leave it alone.
Merino needs washing far less often than cotton. Airing a garment out overnight is usually enough, and several wears between washes is normal. Washing less is better for the fiber and better for the garment's life.
Why less often is the main instruction
Wool manages moisture in a way that gives odor-causing bacteria much less to work with, which is why a merino shirt can be worn for days without turning. The washing machine, not wear, is what ages a garment fastest. Reducing washes is the single biggest thing you can do to make one last.
What actually causes shrinking
Wool fibers have microscopic scales. Heat, moisture and agitation together make those scales lock into each other permanently, which is felting, and it is what people mean when they say wool shrank in the wash. Any one of the three alone is usually survivable. All three together are not.
That is why the instruction is cold water and a gentle cycle. It removes two of the three conditions.
What to avoid
- Hot water and hot dryers. The most common way to ruin a wool garment.
- Fabric softener. It coats the fiber and undoes the properties you bought it for.
- Bleach. Wool is a protein fiber. Bleach attacks it directly.
- Wringing. Press water out gently rather than twisting.
Drying
Lay flat on a towel and reshape while damp. Hanging a wet wool knit lets its own weight pull it out of shape. Wool dries faster than people expect, because it moves moisture as vapor.
Pilling
Some pilling on a new knit is normal, particularly where a bag strap or a seatbelt rubs. It settles after a few wears. A fabric comb or a sweater stone removes what is there without damaging the fabric. Worsted spun yarn, which is what our fabric uses, pills considerably less than woolen spun.
Storage
Fold rather than hang, so shoulders keep their shape. Store clean, since moths are attracted to body oils and food traces rather than to wool itself. Cedar or lavender in a closed container works well for long storage.
Spot cleaning
For a small mark, cold water and a little gentle soap on a cloth, blotting rather than rubbing, will usually handle it and saves a full wash.