Sphagnum moss. I've got two trays that are growing slowly. We're predicted to have several nights of below-freezing temperatures and it appears that people who grow it don't worry about freezing temperatures but I think I'll move it inside our open-ended garage for a little bit of protection, anyhow.
I've got two, roughly 16"x12", trays. One is roughly 3" deep and the other around 2" deep. When I received the plugs of moss I simply set them in the trays "sunny-side-up" with no substrate in the bottom of the trays. They appear to have grown a bit but nothing excessive. I've sprayed them once (recently) with Maxsea and they "seem" to have greened up a tad. When I received the moss it was during a very dry period this past summer and the moss was tan-colored with a few areas or specks of pale green scattered in it. I've simply kept up to an inch, usually 1/2" of water in the bottom of the trays except when it rained and it would fill up higher and then I'd drain it off. I tried a pan of sphagnum prior to these and used a thin layer of peat moss in the bottom...the sphagnum did not do well and it died...seemed like the sphagnum soaked up LOTS of tannins.
The question (this didn't end up being a condensed version, did it? ) is: Do I need some type of substrate below the moss? I'm not gungho about using peat moss, but what about sand or gravel? I've even seen boxes set up using perlite or foam board that is covered with a cloth with the ends of the cloth dangling in the water and the moss on top of the foam getting it's moisture from the wet cloth...it stays moist but not standing in water.
Anyhoo....thoughts on a substrate for sphagnum moss, anyone????