Morning chill at the mountain hut, hiking with a heavy backpack, wind on the ridge, and a long break - in just one day, your body goes through several different conditions. That is why merino clothing is such a frequent choice for trekking, camping, and multi-day trips. However, it does not replace an entire clothing system. For it to work as intended, you need to choose the right fabric weight, cut, and the other layers.
Merino clothing - what does it offer in the field?
Merino wool has a natural ability to absorb some moisture from the skin's surface and transfer it away. In practice, this means greater comfort during a hike, when your pace changes every few minutes. The material helps limit the feeling of being chilled after exertion while at the same time not causing the same rapid feeling of overheating as a thick, non-breathable layer.
The second significant feature is the reduction of unpleasant odors. A merino shirt after one or two days in the field usually requires less frequent washing than a typical cotton shirt. This is a concrete benefit for a trip with a small backpack, a bike tour, or a multi-day trek where the number of spare clothes must be limited.
Merino also works well when the material is slightly damp. This does not mean you can ignore rain, sweat, and the need to change after an intense hike. It does mean, however, that a thin layer next to your skin still provides noticeable comfort before you manage to set up a tent, put on a dry sweatshirt, or prepare a warm meal.
It is worth remembering its limitations. Merino wool usually dries slower than thin synthetic materials, especially in the cold and in high humidity. It is also more susceptible to mechanical damage than thick workwear. For a bushcraft trip, where you often work with wood, carry equipment, and sit on rough surfaces, a blend of merino with synthetic fibers may be a better choice than very delicate, pure wool.
Merino fabric weight and type of activity
The most important parameter when purchasing is the fabric weight, expressed in g/m². It does not tell the whole story about the quality of the knit, but it well defines whether a given item will work as a light active layer or rather as insulation for colder conditions.
120-150 g/m² - summer, running, and intense hiking
The thinnest merino clothing is intended primarily for warm days and high-intensity activities. A shirt of this weight will work well on a summer trail, while cycling, during a fast march with a small backpack, or as a travel shirt. It is light, takes up little space, and is easy to wash in the field.
You have to count on the fact that a thin knit does not provide much protection against the cold. After stopping at a mountain pass or after sunset, you need a sweatshirt, a windproof jacket, or both layers. Do not expect that a 150 g/m² shirt alone will replace a thermal layer.
160-200 g/m² - a universal choice for trekking
For most people planning trekking from spring to autumn, a mid-range fabric weight will be the most practical. 160-200 g/m² shirts and long-sleeves are light enough for hiking, while at the same time clearly better at handling a cool morning, shade in the forest, and windy weather.
This is a good starting point if you are putting together your first set. A short sleeve will work well during high activity, and a long sleeve provides additional protection against the sun, chafing from backpack straps, and the cold. For a multi-day trip, it is often more sensible to have one merino shirt and a second quick-drying synthetic shirt than two identical wool models.
200-260 g/m² - cool days and a slower pace
A higher fabric weight fits well for autumn trekking, winter walks, snowshoeing, and camping trips where you spend a lot of time without intense movement. Leggings, sweatshirts, or long-sleeves from this group can act as warm base layers.
During a strenuous climb with a heavy load, however, thicker merino may turn out to be too warm. This applies especially to people who sweat easily. In such a case, it is better to choose a thinner base layer and only add a sweatshirt during a break, instead of hiking in clothing that is too thick.
How to build layers with merino?
Merino is best used next to the skin, as the first layer. Its task is to manage moisture and reduce discomfort during variable exertion. Above it, there should be an insulating layer, most often a fleece jacket, a light synthetic sweatshirt, or active insulation. On the outside, protection against wind and precipitation is needed: a softshell jacket, a windbreaker, or a membrane jacket - depending on the forecast and the terrain.
For an autumn trek, a practical set can consist of a 180 g/m² merino shirt, a light fleece, and a raincoat in the backpack. When the temperature drops, merino leggings under trousers, a hat, and gloves are added. For a winter camp, it is worth having a separate, dry set for sleeping. The underwear you hiked in all day, even if it does not smell strongly, will contain moisture and will draw heat away faster once you stop.
Do not put on all your layers at once. Before a climb, take off your sweatshirt before you start sweating. During a break, put it back on immediately, and in strong wind, add the outer layer. Such organization works better than trying to find one shirt suitable for every moment of the expedition.
Merino shirt, underwear, or socks?
If you are buying your first item, a short or long-sleeved shirt is usually the best choice. It has the greatest impact on comfort while hiking and is easy to match with the rest of your wardrobe. A long sleeve will be practical in the mountains, in the forest, and where protection against the sun and insects counts.
Merino socks are a very good addition to trekking boots, but they require a proper fit. A sock that is too thick in a tight boot can cause pressure, numbness of the foot, and blisters. For light summer shoes, choose thinner models, and for high boots and colder conditions - thicker ones with reinforcement on the heel and toes. For a trip, it is worth taking at least two pairs and changing them when they get soaked from rain or sweat.
Merino underwear works well for multi-day trips, in the cold, and during travel without easy access to laundry. In summer, during very intense exertion, some users prefer quick-drying synthetic underwear. There is no single answer here - temperature, hiking pace, and whether you can dry your things overnight all matter.
What to pay attention to before buying?
Check the material composition. Pure merino will feel soft and natural, but the addition of polyamide, nylon, or elastane often increases durability and improves the fit. In socks, such an addition is particularly recommended, because that is where the material works under the greatest load.
The fit should be close to the body, but not restrict movement. A shirt that is too loose works worse with subsequent layers and can roll up under a backpack. A model that is too tight will restrict the shoulders and show moisture faster. Before buying, check the back length - when wearing a backpack, a shorter shirt may slide out above the hip belt.
Pay attention to the seams in areas of contact with backpack straps. Flat seams and a well-thought-out cut reduce the risk of irritation on the shoulders, under the armpits, and at the hips. In the case of leggings and long johns, also check that the seams do not run through areas that will be pressed by a harness, hip belt, or trousers.
How to wash and dry merino in the field and at home?
Merino does not need to be washed after every use. If the shirt is not heavily soiled, it is enough to air it out after returning to the tent or hut. This is a practical solution for trips, but it does not exempt you from regular washing after a few days of intense activity.
At home, use a mild detergent for wool and a low-temperature program in accordance with the manufacturer's label. Avoid softeners and high drying temperatures, as they can weaken the fibers. In the field, wash by hand in lukewarm water, gently squeeze out excess moisture, and dry in an airy place. Do not wring the material aggressively and do not place it directly on a hot heat source.
Well-chosen merino clothing is not meant to be the only answer to the weather. It is meant to be a reliable base layer that will allow you to react faster: take off a sweatshirt before a climb, add insulation during a break, and keep a dry set for the night. It is precisely such small decisions that most often determine comfort after many hours away from the mountain hut.