Might be hard to find Hygrolon in the USA now-a-days. I experimented with this product in the past (along with Epiweb & Ecoweb) for growing emersed aquatic mosses.

Was fairly pleased with the results of Hygrolon. Took awhile for the moss to get a "toe-hold". Used in vertical mounts for my applications. Had a tray of water under the mount. The material wicked and held water fairly well to a height of about 10", holding moisture evenly. This product is sort of like a cloth material (some type of woven synthetic material I presume).

The Epiweb & ecoweb did not seem to hold (and/or wick) water unless I was spraying or misting on a very regular basis - water drops would hold within the web structure of the material by doing so. Probably poor with water retention because the material is some type of non-woven plastic.

I think Hygrolon can still be acquired in Europe, and maybe off eBay. There used to be an online site (Folius.com) that use to sell this product, but not anymore. They are carrying a product that is a Hygrolon alternative (a very similar product) called "Spyra". Might be worth checking out if pursuing further for a growing medium.

Lots of good pictures when you Google 'images hygrolon'.

Yeah I think it's a Swedish thing but the website's not very clear on weather or not they sell it or how to get it here. I have seen some great results on Youtube but the guy who used it said the whole setup was pricey. Plus the moss mix he used might be hard to find around here.