Some Thoughts on Sphagnum Cultivation
I've been doing some reading the last few days, trying to learn a bit more about mosses in general; how they grow and propagate, how much their environment affects them, etc.
Turns out that most "typical" mosses do not, in fact, leech nutrients or food from the soil...at least, not intentionally. They do absorb dissolved solids when they come into contact with "tainted" water, but the food and energy necessary for them to grow is produced solely through photosynthesis, with only three necessary requirements that need to be met; Light, water, and warmth (some can continue growing in temperatures as low as 20F). In nature (or cultivation), all the soil represents is an anchor for the moss, nothing more. Similarly, the PH values of the soil can vary widely, again because the moss has very little actual interaction with it, since it it typically situated on top of the soil, and therefore "upstream" of the water flow (rain).
Now, most of the growing guides for sphagnum I've seen want a substrate layer of peat no less than several inches deep, I'm guessing in an assumption that the sphagnum needs to extract some essential nutrients from it. I'm now wondering how important this actually is.
For a period of over a year, when I first began my first sphagnum culture outside of top-dressings, I was mighty low on soil, and lazy. Turns out this wasn't necessarily a bad thing. The end result is that I have a 3 gallon container filling with healthy sphagnum atop a layer of peat/sand no more than 3/8" deep.
Now, at this point, I find it very unlikely that the moss is extracting anything of value from the soil, and aside from 2 test sprayings of diluted maxsea early last year, the colony has been given nothing but distilled water. The fertilizer treatments, by the way, did not seem to make any difference in growth-rate, which is why I stopped, but considering the conditions of the colony at the time (small), and the low light levels, that is not a satisfactory test. I only mentioned it for transparency (i.e. I introduced nutrients manually as a foliar spray at one time).
Now that I'm in a position (or soon will be) to begin a much larger colony for potting purposes, I'm seriously doubting the efficacy of wasting several pounds of peat in order to grow a large tub of the stuff. If all the sphagnum needs is something to anchor to, packed play-sand may work just as well, or bark mulch, or anything else that will retain sufficient moisture and a provide a solid substrate for the initial strands to attach themselves to.
Just put the sphagnum in a tray and water, it's that simple.
I have never heard about using peat to grow Sphagnum. Most of my cultures only have a few strands of moistened LFS as the substrate, and I've even gotten a few cultures started by tossing nothing but a wad of live Sphagnum into the container and keeping it moist and humid.
Hi Zath , I have a few great sphagnum colonies growing and they have no substrate at all , they have never been fertilised and are watered with rain water. I also am now growing darlingtonia in a tray of pure sphagnum and its growing crazy, too fast really the pitchers are just literally poking out the top, also no ferts have ever been used, and the darlingtonia tray is in pretty much full sun and open to the elements more or less in an open fronted propagator ,
Last edited by corky; 10-12-2015 at 09:43 AM.
You may find these of interest Zath.
British Bryological Society
My Sphagnum culture lives on the top of the plastic benches, stuffed between the Nepenthes pots. Of course, you can no longer see the pots because of the Sphagnum, but that's neither here nor there ;-)
This is a funky little thing I'm doing, sphagnum sitting in peat on top with a later of water underneath so that there's very little evaporation from the tray itself, strands of sphagnum go down into the reservoir
Just started it so it's not exploding with growth just yet