A secondhand garment has already survived everything its first owner did to it. What happens next is up to you, and the decisions that matter are made in the first hour: whether you wash it before wearing it, how you wash it, how you dry it, and where it lives afterwards.
Treat every new arrival as a quarantine case
Wash or air everything before it goes into your wardrobe. This is partly hygiene and partly pest control: moth eggs and larvae travel on secondhand wool, and a garment that arrives carrying them will share them with everything hanging beside it.
For wool, cashmere and other animal fibres, you do not need to wash immediately. Airing the garment for a few days on a hanger in a cool, ventilated room, then sealing it in a breathable cotton bag for a week, is usually enough to make sure nothing has come with it. For anything that can be washed, a cool wash does the job.
Read the care label, then decide whether to trust it
Care labels record what the manufacturer recommended when the garment was new. On an older garment, that advice may be decades old, and the fibre may have weakened since. Labels also sometimes describe the safest legal position rather than the best method — dry clean only appears on a great deal of clothing that survives careful hand washing.
The useful rule is: the label is a good source of information about fibre content, and a conservative source for everything else. Where the label says dry clean and the garment is valuable, structured, lined or unstable, follow it. Where the label says dry clean on an unlined cotton or wool knit you paid very little for, hand washing in cool water is often the better and cheaper choice — just accept the small risk.
Sort, test, then wash
Sort by fibre, not by colour alone. Wool and silk behave differently from cotton and polyester, and one hot wash with the wrong neighbours can felt a jumper permanently.
Test colourfastness on anything with strong colour or multiple colours. Damp a hidden area inside a seam or hem with cool water, press with a white cloth, and see whether dye transfers. If it does, wash alone, in cold water, with minimal agitation, and do not soak it.
Use less detergent than you think. Detergent residue attracts dirt and holds odour. Avoid biological detergents and fabric conditioners on vintage wools and silks: enzymes attack protein fibres, and conditioners coat them, flattening the handle.
Fibre by fibre
Wool and other animal fibres. Cool or lukewarm water, a gentle detergent, minimal agitation and no temperature change mid-wash. Agitation plus heat plus alkalinity is what causes felting, and felting is irreversible. Never wring or twist. Press water out against the side of the basin, roll the garment in a towel, and dry it flat and reshaped.
Silk. Cool water, mild detergent, short soak, no rubbing on the surface. Older silk can be fragile, especially where it has been exposed to light and deodorant, and it can shatter — literally tear under its own weight — when wet. When in doubt, wash it less.
Cotton and linen. The tough ones. They tolerate warmer water and more agitation, though older cotton can be thin and older linen can develop weak points along creases. Linen improves with wear but cracks at hard folds.
Synthetics. Resilient and quick-drying, but prone to holding odours and attracting oil. Lower heat, and air-dry where possible; heat is what keeps stains in synthetics.
Blends. Treat according to the most delicate fibre in the mix. A wool-heavy blend gets wool treatment even if the label lists synthetics.
Refreshing without washing
You do not have to launder everything every time it has been worn. Airing a garment overnight in a ventilated room, brushing wool with a soft bristle brush in the direction of the nap, and steaming rather than ironing will remove most surface odour and light creases. Steaming also kills moth larvae that live near the surface, which is why it is worth doing to secondhand coats and jackets that cannot be washed.
For a quick fix on a garment you want to wear tonight, a wash is the wrong answer; airing and steam is the right one.
Stains: act early, avoid heat
The general principles matter more than the specific remedies.
Blot rather than rub, work from the outside of the stain inwards, and use cool water first. Hot water and tumble drying set stains, particularly protein stains like blood, egg and milk. Deodorant and antiperspirant stains are often partly fibre damage rather than stain, so they lighten but rarely vanish. Rust, from metal buttons or hangers left in damp storage, is very difficult to remove without damaging the cloth around it.
Drying
For everything except the hardiest cotton, dry flat or hang in the shade. Direct sun fades dye and weakens fibres, and hanging a soaked wool garment distorts it. Knitwear should always dry flat; a heavy wet knit on a hanger grows at the shoulders and never recovers.
Avoid the tumble dryer entirely for vintage. It shrinks, it pills, it abrades, and its effects cannot be undone.
Storage
Store only clean garments. Dirt and body oils attract moths and set into creases over a season.
Hang structured garments on shaped hangers at the shoulders, fold knitwear, and give delicate items plenty of room. Plastic covers trap moisture and should be replaced with cotton bags, or nothing at all. Cedar and lavender discourage moths without poisoning the air you breathe, and neither works if the garment is stored dirty. Check the wardrobe once a season: the sooner you find a small hole, the smaller the repair.