Sphagnum (Sphagnum) belong to the Sphagnaceae family and look like moss. Sphagnum is part of the peat and that is why it is found in potting soil sold in stores. Attention, it is not ecological!
What is Sphagnum?
There are many sphagnum species found in peat bogs. Their main feature is to be able to store large quantities of water, including in the dead parts of the plant. For example, it is estimated that 1 kg of sphagnum moss can absorb 70 to 75 liters of water!
Sphagnum are fibrous, they also lower the pH of peat bogs and make them more acidic: they are the ideal substrate of orchids but also of laiches and carnivorous plants.
Sphagnum consists of a main stem with leaves growing directly on this stem and twigs forming like bundles, also bearing leaves. So, we are dealing with two types of leaves and two types of cells:
- chlorophyll cells or chlorocysts: living cells that are very green and small, located on the upper part,
- hyaline cells or hydrocysts: dead cells, larger and dull, but which continue to store water through pockets that are tight after the death of the cell.
The flower head or apex, located at the top of the plant consists of an apical bud, which will grow continuously but slowly (3 cm / year) and redo leaves underneath. Only the top of the stems remains alive, the base dies. These dead organic matter (or fossils) accumulated thus form the peat bog.
Sphagnum, which is therefore the upper part of the bog, just above the white peat, is a very rich ecosystem that has an influence on the water cycle given the absorption capacity of the plant.
Sphagnum threatened with extinction
Like all peat bogs, Sphagnum mosses are threatened because drainage destroys wetlands. In addition, the massive use of nitrogen by farmers who put chemical fertilizers in their fields, does not mix well with the cellular development of Sphagnum.
To avoid using sphagnum, replace it with coconut fiber in your soil that will be just as airy. If you have to make a wall or a green roof, you'll probably need Sphagnum: Chilean Sphagnum, Chile's fastest-growing sphagnum, is preferable because peatlands regenerate faster and more easily than European peat bogs. offering the same advantages, namely humidity, aeration of the earth, root stimulant.
(Photo 2: By Bernd Haynold - selbst fotografiert - own picture, CC BY-SA 3.0)