Reference point
A mossy rock in a shady, damp spot; scrape a little moss off and smell.
Do this before you read on. An entry only works when you have just smelled the thing.
Damp, dark green, slightly musty, with a mineral note from the stone underneath. It is low and does not spread far.
Dry moss and damp moss are two different smells. Dry moss is almost mute; only when there is water can the compounds get out. That is why this smell exists only in the shade and only after rain.
In European perfumery, oakmoss is one of the foundation materials of an entire family of fragrance. Stone moss is not like oakmoss, but it is the closest reference you can smell for understanding that group of smells.
How to smell it
Find a rock or wall covered in moss in a shady spot after rain. Scrape a little moss into your palm, squeeze it gently and smell. If the moss is dry, add a little water and wait thirty seconds.
Why this one is hard
Because it is very weak and easily overtaken by the smell of the surrounding soil. You have to scrape the moss off the surface and smell it on its own.
Don’t confuse with
This entry
Stone moss
Earthy family
Both contain geosmin. First rain has a cold mineral note and comes from the air; stone moss is darker green, lower, and has to be scraped off to be smelled.
Scientific note
Moss has no roots and takes up water directly through its surface, so it lives with a thick layer of microorganisms. Most of what you smell comes from that microbial layer rather than from the moss itself — mainly geosmin secreted by Streptomyces bacteria, the same compound behind the smell of first rain.
In Vietnamese life
In Vietnamese culture, moss and mustiness are associated with age and abandonment, and usually carry a negative meaning. In European perfumery the same kind of smell is considered luxurious and classic — a clear example of the value of a smell being set by culture.