The Sphagnum medium is one of the last species of Sphagnum discovered.
As for the Sphagnum magellanicum and S. divinum, is one of the largest species of sphagnum moss.
It is widespread in Central/North-Europe and it characterizes the bryophytes vegetation of large peat bogs. It has a very fast growth capacity which, together with the robustness of the species, makes it ideal for growing with bigger plants. Sometimes you may need to "prune" the sphagnum, if it had grown to incorporate the rhizomes of the plants. When exposed to direct sunshine acquires a crimson red colour and the heads will form a very compact “carpet”.
Although it is common in northern Europe, in the past it has always been confused with S. magellanicum. Analysing the populations of Sphagnum previously identified as magellanicum, it was possible to understand that the European populations actually belong to two different species*: S. divinum and S. medium, which are slightly different from the original S. magellanicum, which is located only in South America.
In particular, the S. medium differs from the S. divinum because of the large pores at the base of the leaves, and a thick wall of photosynthetic cells (see pictures).
Clone P35 comes from Estonia and has shown under a microscope both connotations, on some (but not all) of the analysed leaves. In any case, it is quite certain that the correct identification is Sphagnum medium.
Clones Detail:
P35 - Location Estonia - During the winter months it acquires an intensely red color
Notice: The clone P35 was previously identified as Sphagnum magellanicum in this catalogue. For those who bought it previously, it is sufficient to change the name of the species.
Sources:
*Hassel, Kristian, et al. "Sphagnum divinum (sp. nov.) and S. medium Limpr. and their relationship to S. magellanicum Brid." Journal of Bryology 40.3 (2018): 197-222.