Peat moss products shelf life.

The minimum shelf life of the substrate is 6 months, but in unheated rooms it is 12 months.

Peat substrates are natural products based on 98% organic matter and enriched with microbial activity. To ensure optimal substrate quality even after a certain storage time, avoid the negative effects of sun,  temperature and rain. It is recommended to consider the following hints for storage.

Best suitable condition for the storage of peat:
· Never stock in direct sunlight – try to stock below 25 °C
· Protect pallets with black nets against sunlight (UV stable)
· If possible, please stock inside (no sun, no rain)
· Follow strictly “Fi-Fo” > First in, first out
· Bulk deliveries stored inside or protected by clean plastic film
· Propagation substrates use “as fresh as possible”
· Never stock bulk substrates inside the greenhouse.

Loosening up and mixing of compressed substrates.

Substrates in compressed bales (either 250 L or Big Bales) require some gentle loosening up before use. It is not necessary to mix the substrates any further as it is already a homogeneous, ready to use mix. A small amount of water should be added to ensure optimal moisture for potting/tray filling.
Before use the following should be checked:
1. For transplanting a humidity level of 60 –65 vol.-% is ideal.
This allows best handling while potting/tray filling, it avoids a transplanting “shock” and it is easy to rewet.
2. Put some substrate in your hand. If you are able to blow it away easily, it is too dry.
3. 8 L of water per 200 L bale is usually sufficient to bring back the moisture to an optimal level.
4. Optimal moisture is given if you are not able to press out water by hand, but you can hear squishy sounds
when pressing the substrate in your hand close to your ear. The humidity level is then optimal. The substrate
should keep its shape after being compressed by hand.

Presence of Mold

Mold is usually created by the growth of filamentous fungi. If the water content is high enough, these organisms will grow on almost any type of organic matter. Any of us have seen mold on bread if it has been in a warm and wet place for long time enough. While the sight of mold growing on a freshly opened peat moss substrate bag may seem desperade, they are not pathogenic to plants. There are numerous species of fungi, and those found in peat moss are mostly saprophytes, meaning that they only feed on decomposing organic matter.  In addition, it can be said that some of these microorganisms can even have beneficial effects on plant growth.

The Benefits of Microorganisms in Sphagnum Peat Moss

Sphagnum peat moss contains numerous different microorganisms that occur naturally in peat bogs.  The presence of a healthy community of microorganisms in sphagnum peat moss makes it more difficult for root rot organisms to establish, because the inoffensive saprophytes compete with the pathogens for available resources. Moreover, some species are known to synthetize molecules that are quite effective at suppressing some root rot pathogens though various modes of action. The microorganism population in peat varies depending on several factors, including the harvesting site. White, light brown, high quality peat typically has a more diverse and healthy population. It is therefore more susceptible to provide disease suppression as well.


In unused peat moss based growing media that have been stored for a prolonged period, some mold may be seen on the external layer of the mix. Wet condition can build up in this area of the bale, which generates optimal environment for fungus development. Mixes with high fertilizer charges or those that are exposed to high temperatures during storage are more at risk to develop mold, but it can occur on almost any peat moss based product.


After opening the packing there was fungus on the surface.  What needs to be done?
Pure peat provides an organic matter content of up to 98%. Organic matter attracts fungi. Peat is enriched with lime and fertilisers to make it a growing medium. These additives improve living conditions for microorganisms. Saprophytic fungi (and bacteria) living on dead plant material as well as airborne spores, always present in the environment, are able to enter the peat at this stage. Substrate packagings showing fungal growth should be opened up and mixed thoroughly in order to aerate as much as possible. After aeration, the fungus mycelium collapses quickly. The fungal mycelium provides no harm to the crop at all as the fungi are purely saprophytic. Fungal growth on substrate surfaces in the greenhouse is supported by moist conditions and usually originates from airborne spores. All measures, preventative and curative, should therefore create a drier surrounding and ensure good aeration of plants and substrate. Implement a dry crop cultivation to allow the surface of the substrate to dry down. If possible, reduce relative humidity inside the greenhouse. There is no effective fungicide
available on the market against saprophytic fungi. Fungicides against soil-borne pathogenic fungi show very little effect.