What is peat?

Peat is an organic, sedentary deposit (growing from bottom to top) that consists predominantly of dead, humified plant material. This plant material has not yet decomposed completely due to a lack of oxygen caused by water repletion and therefore the structure is at least partly still recognizable.

It is mainly distinguished between white and black peat. The botanical structure of the peat forming plants can still be recognized well in light yellowish brown to dark brown-colored white peat. Black peat is decomposed more strongly than white peat. The most important plants for bog formation are sphagnum moss (Sphagnum spp.) and cotton grass (Eriophorum vaginatum) which makes up the fibers in the peat. Brown/black-colored black peat consists of the plant structure being largely decomposed. There are also transition bogs that blend in the ecological conditions of the high and low moors.

Peat can be compared with a sponge in its structure; it is not very firm and has a high pore volume. Despite a high water holding capacity due to the middle and fine pores, a high air capacity is also given by the large share of coarse pores. With increasing decomposition, the cavity volume (the pore share) decreases and the amount of firm substance (the bulk density) increases. The water holding capacity rises simultaneously and the air capacity gets lower. The more strongly decomposed peat retains more water; it is, however, simultaneously less "spill proof". On the other hand, peat decomposed more strongly has a higher exchange capacity when referring to volume and can thus store more nutrients. The increased buffer capacity towards pH adjustments can also be positively assessed. The pH itself and the contents of soluble nutrients are not influenced by the degree of decomposition.