The short answer is that high quality merino wool won’t itch.
When you think of wool clothing, you may well think of itchy, uncomfortable clothing that scratches.
The reason that wool can be itchy depends on several factors.
Wool Diameter Size
Wool is scored according to the diameter of the fibers. The broader the diameter, the more likely the wool is to be itchy and scratchy. The reason is that thicker fibers don’t bend when pressed against the skin, so you’ll feel them when you move.
Merino wool has very low diameter fibers compared to normal wool, so it feels smooth and soft against the skin.
Not all Merino wool has the same diameter, though.
Here’s a chart for the different sizes:
|Extra fine||< 19.5|
|Strong||22.6 < 24|
Taken as a general rule, you’ll start to find merino wool start to get more scratchy when the micron size goes above 22 microns, which is medium grade. Anything above 30 microns will be itchy. The world record is currently 10 microns!
Most of the reputable braands for for ultra-fine wool, or 17.5. You’ll find that cheaper brands user high micron diamaters, which can start to itch.
What should I do if I still find Merino Wool itchy?
Some people recommend wearing a silk baselayer with merino on top for insulation, if you don’t like having wool close to your skin. It’s also a good option if you find capilene (a polyester based fabric from Patagonia).