Washing a Wool Blanket: How to Keep Lamb’s Wool Soft and in Shape

A guide to woven wool blankets made from lamb’s wool and virgin wool: machine or hand washing, which detergent to use, how to dry them, and what helps with lint, odours and moths. Not for fleece, not for cashmere, not for felted blankets.

A wool blanket needs to be washed less often than most people think, and it handles the washing machine better than most people fear. Wool hardly absorbs odours because the fibres are naturally coated with lanolin. Two nights out in the fresh air replace a wash cycle in most cases. If it really needs washing, three things determine the result: temperature, movement and drying.

Air it out first, then wash it

Wool is self-cleaning as long as the lanolin remains on the fibres. If a blanket smells of smoke, cooking or dogs, hang it outside overnight on the balcony or by an open window. Damp air helps more than dry air because the fibres absorb moisture and release the odour with it. Only when airing it out isn’t enough or there is a stain should the blanket go in the machine.

Every wash cycle washes out some of the lanolin. This is no reason never to wash it, but it is a reason not to do it every month. Once or twice a year is enough for normal use.

In the washing machine: wool cycle, 30 °C, no fabric softener

Woven wool blankets such as the Klippan wool blankets are suitable for machine washing. The rules are simple, but every single one is important.

• Cycle: wool cycle or hand-wash cycle. Both move the drum slowly and infrequently. Movement is the reason wool felts, not temperature alone.
• Temperature: 30 °C, never higher. And do not rinse with cold water if the main wash was warm: the temperature shock causes the fibres to felt.
• Detergent: liquid wool detergent without enzymes. All-purpose detergent contains proteases that attack wool because wool is a protein.
• Fabric softener: none. It leaves a film on the fibres and makes the blanket dull instead of soft.
• Spinning: maximum 600 rpm, 400 is better. The blanket comes out of the drum wet and heavy; this is normal.

Wash the blanket on its own, without other laundry. Zippers and buttons from other items rub against the fabric and pull out threads.

By hand: lukewarm, do not rub, do not wring

If you do not have a machine with a wool cycle, wash it in the bathtub. Use lukewarm water, a dash of wool detergent, leave the blanket to soak for ten minutes, then press gently. Do not rub, wring or knead. Rinse twice with water at the same temperature. Finally, roll the blanket in a large towel and press out the water.

Drying: flat, in the shade, never in the dryer

The dryer is the most common cause of a ruined wool blanket. Heat and movement together felt the fibres in a single cycle. Instead: lay the blanket flat on a drying rack, pull it into shape, and let it dry in the shade or indoors. Hanging on a line will make it longer at the hanging point because wet wool is heavy. If you do not have a flat surface, fold it over two bars and turn it after a few hours. Direct sunlight bleaches the colour, especially in reds and oranges.

Lint, pilling, fringes

A new wool blanket sheds lint in the first few weeks. These are loose fibres that were not incorporated during weaving, not a material defect. Most of it disappears after the first wash. Pilling, or small little balls, is caused by rubbing against clothing and sofas. A wool comb or a fabric shaver on the lowest setting removes them without damaging the fabric. If the fringes are twisted after washing, straighten them while wet and let them dry that way.

Stains: immediately, cold, with patience

Blot liquids off immediately with a cloth; do not rub. Rinse red wine and coffee with cold water, never warm, because heat sets protein and tannins in the fibres. Apply a little wool detergent directly to grease stains, leave it to work for ten minutes, then wash the whole blanket. Stain removers with oxygen bleach are not suitable for wool.

Moths: clean wool in cotton

Clothes moths lay their eggs in wool that smells of skin, sweat or food. A washed blanket is of no interest to them. For this reason, the blanket should be washed or thoroughly aired out over the summer and stored in a cotton bag or pillowcase, not in plastic. Cedar wood or lavender in the wardrobe keeps moths away but does not kill larvae. If you find holes, wash everything out of the wardrobe and freeze the affected blanket for a week.

Good to know: A felted blanket cannot be restored. Wool felts because the scales on the fibres hook into each other when exposed to heat and movement. This process is irreversible. Therefore, the rule for wool is: when in doubt, colder, slower, shorter.