Wash merino wool on a cool, gentle cycle with a wool-safe detergent and dry it flat. Don't tumble dry — heat is the main cause of merino shrinking. Done correctly, a quality merino base layer will last years of regular wear.
How do you wash merino wool?
Use a cool wash (≤30°C) on a wool or delicate cycle, with a wool-specific or mild detergent. Skip fabric softener — it coats the fibres and reduces breathability and moisture-wicking. Hand washing is fine but isn't necessary for most modern merino garments.
Can you put merino wool in the dryer?
No. Tumble drying is the most common cause of merino shrinkage and pilling. Heat and agitation together felt the fibres, which permanently shrinks the garment. Dry merino flat on a towel, away from direct sun and heat sources.
Will merino wool shrink?
Untreated merino can shrink in hot water or a dryer. Most quality merino base layers (including ours) are machine-washable wool, treated to resist shrinkage in normal cool washes — but the dryer is still off-limits. Stick to cool wash, flat dry, and your merino keeps its shape.
How often should I wash merino wool?
Less often than synthetics or cotton. Merino is naturally antibacterial — odour-causing bacteria don't thrive on the fibre. For most use, airing a base layer between wears is enough. Wash when it's actually dirty, sweaty, or starting to feel less fresh after airing.
How do I get rid of smells in merino wool?
Air the garment outside (or in a well-ventilated room) for a few hours. For most "end of day" smells this is enough. If a wash is needed, use cool water and a wool detergent — hot water can set odours into the fibre rather than removing them.
How do I store merino wool?
Fold and store flat or loosely on a shelf — don't hang heavy merino pieces, as the weight stretches the shoulders. For long-term storage (off-season), use a cotton bag or breathable container, and add a cedar block or natural moth deterrent. Avoid plastic bags, which trap moisture.
What if my merino gets a hole or snag?
Snags can usually be pulled through to the inside with a needle — don't cut them. Small holes can be darned with matching wool yarn or a wool patch. A repaired merino layer is still a far better garment than a brand-new synthetic one.
Frequently asked questions
Can you iron merino wool?
Generally not necessary. If you must, use a cool iron with a damp cloth between the iron and the fabric. Most merino base layers don't crease enough to need it.
Does merino wool pill?
All wool will pill where it gets sustained friction (under backpack straps, where a jacket rubs). Pilling reduces over time as the loose fibres work themselves out. A wool comb or pill remover restores the surface.
How long does a merino base layer last?
With correct care, a quality 100% merino base layer worn regularly lasts five years or more. Cheap thin merino or merino-synthetic blends generally don't.
Do I need wool-specific detergent?
It's the safest choice but not essential. A mild, fragrance-free detergent on a cool cycle works fine. Avoid heavy enzyme detergents and bleach.
Built to last, made in New Zealand
Smart Merino's Brass Monkeys range is made in New Zealand from 100% merino wool. Cared for properly, your base layers will outlast multiple seasons of synthetics.
