- A merino sweater may be washed by hand or on the wool cycle of the washing machine, always at a maximum of 30 degrees and with a mild wool detergent.
- Merino wool does not tolerate fabric softener, biological detergent, or the dryer. Those three things shorten its lifespan the most.
- Always dry a merino sweater flat on a towel, never hanging. Hanging stretches the shoulders irreversibly.
- Thanks to the natural structure of the fiber, merino wool hardly absorbs odors. Airing it between wears is often enough; washing is only needed once the sweater has actually become dirty.
- At Meedin, every merino sweater is knitted in one piece in the Netherlands, without seams. This construction holds its shape better and can withstand proper washing without any problem, season after season.
- Always follow the washing instructions from the manufacturer on the label of your sweater first. (scan the QR code on the inside of the logo on the Meedin sweater) The advice in this article is general guidance for merino wool; if the care label says otherwise, that always takes priority.
Washing too hot, drying incorrectly, or letting it tumble in the machine too often: a sweater meant to last can sag, shrink, or pill within a single season where it used to be smooth. Washing and caring for a merino sweater is not specialized work. It is just different from cotton. In this guide, you will find what works, what does not, and why. No myths, no excessive caution. Just the steps that keep your wool sweater in shape, from the first wash to summer storage.
Why merino wool calls for care (without making a fuss)
Merino wool comes from the merino sheep, a breed that produces finer fibers than ordinary sheep’s wool. That fineness, usually between 17 and 19 microns in quality yarns, means the fiber does not itch against the skin. At the same time, it makes the yarn more sensitive to heat, friction, and harsh detergents than thicker wools or synthetic blends.
Wool is protein. Not cotton, not plastic. Every fiber has a scaly outer layer that contracts when exposed to a combination of heat, water, and movement. That is what causes felting: that irreversible process where a sweater suddenly feels like cardboard and is two sizes smaller. Hot water plus a heavy wash cycle, and it is done for.
Good news: the fiber itself is resilient and dirt-repellent. Merino wool breathes, springs back into its original shape, and hardly absorbs odors. With normal use, a merino sweater actually needs less care than a cotton shirt. The trick is not doing a lot. It is doing the right things at the right time.
The basic rules for washing a merino sweater
Three things determine almost everything: temperature, detergent, and movement. Keep those under control and you are fine.
Temperature. Maximum of 30 degrees wool wash. No warmer. Some labels allow 40 degrees, but most merino sweaters perform better in cooler water. Cold is fine too; it works well for light soiling. What you must absolutely avoid is changing temperature during washing or rinsing. Switching from warm to cold (or the other way around) is one of the fastest ways to shrink wool.
Detergent. A mild wool detergent. No biological detergent: those contain enzymes that actively break down protein fibers. No bleach. And no fabric softener. Softener leaves a layer on the fiber that blocks thermoregulation and breathability. A sweater that comes out softer because of softener is in fact coated, and therefore pills faster instead of less.
Movement. As little as possible. In the washing machine that means: the wool cycle, short cycle, low spin. Maximum 600 revolutions per minute, preferably 400. By hand: gently submerge, do not wring, do not scrub.
Always turn the sweater inside out before it goes into the drum. That protects the outer side from friction against the drum and other laundry. Never wash a merino sweater together with zippers, jeans, or towels either. Those are exactly the items that cause the abrasion you want to avoid.
Make sure you always follow the washing instructions from the manufacturer on the label of your sweater first. The tips in this article are general guidelines for merino wool, but if the care label says something different, that always matters most!
By hand or in the washing machine?
In theory, both are possible, and both methods work fine as long as you stick to the basic rules. They just have different strengths.
Hand washing gives complete control. Fill a sink or basin with lukewarm water, dissolve a small dose of wool detergent, and let the sweater rest in the suds for a few minutes. Press the fabric gently. Do not wring, do not scrub. Then rinse in clean water of about the same temperature. That last part sounds like a detail, and it is not: a sudden change in temperature is exactly what causes the fiber to tighten up and felt.
The machine also works, provided you choose the wool cycle and use low spin. On the wool cycle, the drum turns less, pauses more often, and uses more water, exactly what wool needs. A wash bag adds extra protection, especially for finer fits. What you should never do: a normal cotton cycle, a synthetics cycle at 40 degrees, or that intensive two-hour wash. The combination of heat and long mechanical stress is exactly what ruins a wool sweater.
A stain does not necessarily mean a full wash. For small spots, spot cleaning works: a lukewarm, damp cloth with a drop of wool detergent, gently dab, do not rub. Dry afterward with a clean cloth. Very often, that is enough.
Drying, folding, and storing
This is where most wool sweaters lose their shape. Not in the washing machine, but in the drying phase.
You do not dry it hanging. A wet sweater will stretch under its own weight, especially at the shoulders, and dry in that stretched shape. One wrong drying session and you will not get that shape back.
The correct approach is simple. Lay a dry towel flat on a surface. Place the sweater on it, and roll the towel up loosely to press out excess water. Do not wring. Reshape the sweater to its original fit on a dry towel or drying rack, flat, out of direct sunlight and away from the heater. A day, sometimes a day and a half. Do not use the dryer, even on the wool or delicate setting. It is still a combination of heat and tumbling that merino wool cannot handle in the long run.
The same principle applies to storage. Fold, do not hang. A merino sweater on a hanger will stretch the shoulders no matter how good the hanger is. Fold it and place it on a shelf or in a drawer. For longer storage, for example after winter, a cotton storage bag works better than plastic. Wool needs to breathe to prevent moisture and musty odors. Add a few cedar blocks or lavender, no mothballs. The smell of mothballs sinks into wool and is hard to remove.
More basic guidance is briefly summarized on our care page.
Prevent pilling, creasing, and loss of shape
Pilling (in English "pilling") is caused by friction. Under the arms, on the lower back where a backpack rubs, at the cuffs that slide over a desk. Pilling is not necessarily a sign of poor quality. Even good merino wool can pill in the first few weeks as loose fiber ends settle on the surface. After that, it decreases.
What speeds up pilling: high spin speeds, fabric softener, tumble drying, and a synthetic lining in a jacket that rubs against the sweater all day. What helps: handle it gently the first ten times you wear it, use a wool comb or fabric shaver for existing pills, and do not wash it unnecessarily often.
For wrinkles, steam works better than an iron. A steamer or the steam function of an iron at a distance of ten centimeters relaxes the fiber without contact. Direct heat on the fabric is risky. If you do iron, do it on the wool setting, with a damp cloth in between, without pressure. Preferably not, if you can avoid it.
Loss of shape is rarely caused by one thing. Usually it is a buildup: once dried hanging, once washed too hot, left on a hanger for a few months. Avoid those three and you will keep a sweater in shape without effort.
Why you do not need to wash a merino sweater as often
One of the practical advantages of merino wool is also one of the least known. The fiber hardly absorbs odor. That is due to the keratin structure, which provides less breeding ground for bacteria than cotton or polyester. A merino sweater worn for a day and left airing out in a ventilated room at night smells almost neutral the next morning.
The practical result: a merino sweater does not need to go into the wash after every wear. With normal use, if the sweater is not dirty, washing is not necessary. Many people wash their sweaters only occasionally. Airing it on a clothes hanger in a well-ventilated space, spot cleaning now and then, and wearing it the rest of the time.
Less washing is not only practical, it is the most effective way to extend the life of a wool sweater. Every wash is a small strain on the fiber, however careful you are. Cut the number of washes in half and you significantly extend the life of your sweater. That is not a trick. It is simply how wool works.
How we look at it at Meedin
We make our sweaters in the Netherlands, in Staphorst, in our own workshop with textile experience dating back to 1955. Every sweater is knitted in one piece (3D knitting), without seams, with about 25 percent less material waste than the classic cut-and-sew process. That has consequences for care. A seamless sweater has no weak points where fabric can tear under tension and keeps its shape better after washing.
We work with 100 percent merino wool, finely spun, without synthetic blends. The downside of this choice: that quality needs a bit more attention than a blended yarn. If you respect the basics, you get a sweater back that does not need replacing after one winter. Our crew neck sweaters and turtlenecks are available in three lengths, because fit also determines how a sweater holds up over time. A sweater that is too short is pulled down every time you put it on; one that is too long stretches under its own weight. More explanation is available in our size and fit overview. The right length is part of care, just like the right wash.
Conclusion
Washing a merino sweater and caring for it comes down to three principles. Not too hot, not too hard, not too often. Dry flat, store folded, wash less often than you are used to with cotton. The rest is habit. A well-made merino sweater will serve you for years if you give it what it asks for. That is not a high price for a garment that sits against your skin every day and does not need replacing every season.