Merino wool basics: why Australians choose it

Merino wool's versatility is increasingly found in wardrobes beyond hiking or cycling gear. Its presence in everyday clothing like tees, base layers, jumpers, and singlets highlights its move from technical gear into everyday merino wool clothing for a reason: what the fibre actually does, not just what's on the swing tag, which keeps readers interested in its practical benefits.

What makes merino different from regular wool?

Is merino wool itchy? Not when it is the right grade. Ordinary wool comes from a range of sheep breeds and varies a lot in thickness. Merino comes from Merino sheep, and the fibre is much finer-usually between 17 and 24 microns, depending on the grade. Anything under 19.5 microns is generally fine enough to sit against the skin without the prickle people associate with a scratchy jumper.

That fineness is the whole story. Coarse wool fibres are stiff and bend at an angle when they touch skin, which is what you feel as an itch. Fine merino fibres are more flexible, so they bend instead of poking. If you have written off wool because of an old jumper, it was almost certainly not merino, or it was coarse and low-grade.

Temperature regulation is the real selling point.

Merino fibre has a natural crimp and a core that absorbs moisture vapour before it turns into sweat on your skin. In practice, that means a merino wool t-shirt feels warm in cool conditions and doesn't turn clammy once you start moving. Merino isn't "warmer" than cotton in every situation; it adjusts across a wider temperature range, which is why it works as a single layer through a Melbourne day that starts at 8 degrees and finishes at 22.

Cotton is fine in flat heat, but it offers little relief once the temperature or your activity level changes, because cotton holds moisture rather than moving it away from the body.

The odour resistance is not marketing spin.

This is the claim people are most sceptical of until they test it. Merino fibre contains keratin-the same protein in your hair-and the surface structure makes it harder for odour-causing bacteria to bind to it, unlike synthetic fibres. Most wearers can get two to three days out of a merino base layer under normal conditions before it needs a wash. That's not an excuse to wear it for a week straight, but it does mean fewer washes over the life of the garment, which helps the fibre hold its shape.

What GSM means on a merino product

You'll see merino garments listed by weight in grams per square metre (GSM). Lightweight merino sits around 150 to 170 GSM and works as a summer base layer or warm-weather tee when you want the fibre's benefits without bulk. Midweight, around 180 to 200 GSM, is where most everyday tees and long-sleeve tops land, and it's the range that suits most of the year across southern Australia. Heavier merino, above 220 GSM, moves into jumper and winter base-layer territory.

Our own merino tees sit at 170 to 200 gsm depending on the style, which is deliberately the range that works from an autumn morning through to a cool evening without needing a second layer.

How to wash merino wool correctly

This is where most people go wrong-usually by treating merino like a normal cotton tee.

Wash it cold, on a wool or delicate cycle, with a wool-safe detergent. Skip the fabric softener; it coats the fibre and reduces the natural moisture-wicking properties that make merino work in the first place. Turn it inside out before washing to protect the surface from friction against other items. Skip the dryer entirely. Heat felts wool fibres over time, which causes shrinking and that dense, matted feel. Lay it flat in the shade to dry instead, and it will be ready within a few hours thanks to how quickly merino sheds moisture.

Done this way, a merino tee holds its shape and softness for years. Thrown in a hot dryer a handful of times, it will feel like a different, worse garment within a season.

Where merino earns its price

Merino costs more than a plain cotton tee because of the raw fibre itself, not markup. Fine-grade merino wool costs more to produce than cotton, and turning it into a fine, soft knit requires more specialised handling than standard cotton. For that cost, you get a garment that performs across more conditions, needs fewer washes, and, if looked after properly, lasts longer than the cotton equivalent.

If you want one tee that covers a wider temperature range and stays fresh on day two, merino is doing a job cotton can't.

Buying merino for the first time

Start with a midweight piece-something in the 170 to 200 GSM range-in a style you'll actually wear often enough to justify the price. A crew neck tee is the easiest entry point because it slots straight into whatever you already wear, no new styling decisions required. As a rule of thumb, look for 18.5 to 19 microns-this is the sweet spot for softness.

Browse our men's merino t-shirts or women's merino t-shirts to see the current weight and colour range, or go straight to the FORT merino short sleeve tee if you want a specific starting point. Check your usual size against our size guide first; merino knits run true to size, but the finer gauge fits closer to the body than a cotton tee of the same size.