How do I wash and look after cashmere?

Cashmere gets treated like an heirloom and it should be treated like clothing. The fibre is finer than merino, around 14 to 19 microns, which is why it feels soft against the neck, and it is also short, which is why loose ends work out of the yarn and pill. Almost every complaint about cashmere — it bobbled, it stretched, it got moths — comes from care habits that suit a woven coat rather than a fine knitted animal fibre.

What you'll need

• a wool or cashmere detergent
• two large towels
• a cashmere comb or fabric shaver
• a mesh laundry bag

Step by step

1. Wash it more often than instinct says.Every three or four wears. Body oil and skin left in the fibre is what moth larvae feed on, what makes the knit look grey and tired, and what eventually sets as a stain. Cashmere is not damaged by careful washing; it is damaged by neglect and by dry-cleaning solvent.
2. Use cool water and a wool detergent.Around 20 to 30 degrees. Never a biological detergent — the enzymes are there to digest protein and cashmere is protein. A dedicated wool wash or a plain non-bio liquid is right.
3. Submerge and squeeze, do not rub.Press the garment gently under the water and squeeze the suds through it for a minute or two. Rubbing two wet surfaces of cashmere together is exactly how you felt it.
4. Rinse at the same temperature.A cold rinse after a warm wash can shock the fibre. Change the water twice at the same temperature until it runs clear.
5. Press the water out in a towel.Lift the garment supporting its whole weight, lay it on a dry towel, roll the towel up and press. Never wring, and never let a soaked cashmere jumper hang from your hand.
6. Dry it flat, reshaped.Lay it on a second dry towel on a flat surface away from radiators and sunlight, and pat it back to its measurements — sleeves straight, body square, ribbing eased back in. Turn it over once when the top is dry.
7. Comb the pills, do not pull them.Lay the garment flat, hold the fabric taut, and work a cashmere comb or a fabric shaver in one direction with almost no pressure. Do this after the first few wears — early pilling is short fibre ends leaving the yarn, and once they have gone the garment settles.
8. Rest it between wears.Give a cashmere jumper a day off between outings and lay it flat. Fibres recover their crimp when they are not under load, and a rested garment holds its shape far longer.

Tips

• Fold cashmere, never hang it. The weight of a wet or even dry knit hanging from two shoulder points stretches the fabric permanently.
• Machine washing is possible on a genuine wool cycle in a mesh bag with a wool detergent and the spin turned down or off, but only on a machine whose wool cycle really does barely move the drum.
• Grade claims — two-ply, Grade A, Inner Mongolian — are unregulated. The things you can actually check are fibre length and density: hold the knit to the light, and a dense fabric with little visible gap between stitches will pill less and last far longer.
• Routine dry cleaning is worse for cashmere than washing. Solvent strips the natural oils from the fibre and leaves it drier and more brittle each time.
• Store it clean, folded, in a breathable bag or box, with the whole wardrobe kept in mind — moths go for cashmere before anything else you own.

Common mistakes

• Hanging a cashmere jumper on a hanger between wears — It is a knit and it stretches under its own weight. Within a season the shoulders bump and the body grows longer.
• Using biological detergent because it is only a small amount — Protease enzymes digest the fibre itself. The damage is cumulative and shows as thinning and a loss of softness.
• Pulling pills off with your fingers — The pill is anchored by fibres that are still part of the fabric, so you take sound yarn with it and thin the knit.
• Putting a worn cashmere jumper straight into storage — Invisible body oil is a moth attractant and oxidises into a yellow-brown stain that develops in the dark over months.

Keeping on top of it

• Hand wash (every 3 to 4 wears)
• Comb or shave pills (as they appear, weekly at first)
• Rest flat between wears (every wear)
• Check stored items for moth activity (monthly in summer)

Questions people ask