Peat, which is the result of an extremely slow process of accumulation, compaction and decomposition of plants that can take 1000 to 7000 years, comes from bogs, natural ecosystems very rich in biological diversity, unfortunately victims of overexploitation.
There are three types of peat, classified according to the degree of decomposition: pale peat, the most recent; brown peat; and black peat, the oldest, particularly rich in organic and mineral particles.
What is the role of peat in the garden?
The benefits of peat are numerous and the use of this fossilized plant material has long been recommended lighten heavy soils or enrich the soil with humus. Peat is also known for its water holding capacity and high porosity.
Where to look for peat in nature?
Bogs, these moist and acidic environments where plant remains decompose very slowly, are abundant in Ireland, Quebec and even Sweden and the Baltic countries. In France, their presence is found in Auvergne or even in Brittany. But there are far fewer bogs in Europe since the Second World War than before.
Why is it important to preserve peat?
It would take about a century to get 5cm of peat…! It is an understatement to say that this natural material is almost non-renewable. However, the benefits of bogs are considerable.
These ecosystems play a vital role in storing carbon, which is responsible for global warming. Logically, on the other hand, their extraction and degradation is responsible for the emission of a significant amount of greenhouse gases.
The bogs are also home to rare and protected fauna and flora: frogs, dragonflies, butterflies, but also carnivorous plants such as sundew. The use of peat involves the destruction of very fragile ecosystems.
What are the alternatives to peat in the garden?
It is important to recognize the value and scarcity of peat, a natural resource that is overused, and choose alternatives where possible:
- home compost;
- a mixture of topsoil and coir;
- a mixture of topsoil and wood fiber compost;
- a mixture of topsoil and substrates based on mineral materials such as perlite or pozzolan (lava stone).