The criteria for purchasing decisions have changed. In addition to the price and properties of the product, environmental aspects are also playing an increasingly important role. Most commercially available potting soil is no longer regarded as safe. It contains large amounts of raised bog peat. Raised bogs, however, fulfill an ecological function and should remain untouched. But the preference for peat persists. Is it really irreplaceable?
What is raised bog peat anyway?
Bogs are water-saturated and oxygen-poor landscapes. Under these circumstances, microorganisms can only very slowly break down the dead plant material into its constituent parts. The only partially decomposed plant material accumulates over time and thus forms the peat. A raised bog is no longer connected to the groundwater and is only fed with moisture from precipitation.
The first stages of decomposition result in the white peat, which is actually light brown. Plant remains can still be seen in it. Black peat is the last decomposition stage that still has the characteristics of a loose soil. Since dried peat is flammable, it was used a lot for heating in the past. Therefore, it is still common today to classify peat according to calorific value. The higher the value, the more the plant material is decomposed.
Properties of raised bog peat
White peat is mostly used for potting soil because it has a coarser structure than black peat. This makes the plant substrate looser. It also contains black peat less often.
Both types of peat are low in nutrients and acidic. This is how low their pH value is:- White peat has a value between 3 and 4
- Black peat has a value between 5 and 6
Why is peat used?
All plants need nutrients for their growth and mostly a not too acidic environment. Peat has neither to offer. It is therefore surprising why it has become so widespread. However, it has been inexpensive for decades, which makes it attractive for retailers. Added to this is the effortless dismantling as well as simple packaging and transport. The following reasons are also given for its use:
- good starting material, due to uniform composition
- its structural stability gives plant roots a hold
- can store and release water and nutrients
- is largely free of pathogens and seeds
- the loose structure offers a good supply of oxygen
A lack of nutrients and a low pH value are not an insoluble problem for industry. Nutrients are simply added in the desired composition and concentration. And by adding lime, the acid is neutralized.
Note: The mining operations do not provide any financial compensation for the destruction of the raised bogs.
Self-mixed plant substrate
If you mix up your soil yourself at home and use peat for it,
your plants can benefit from its physical properties such as looseness and structural stability. But you also have to find a solution for the "acidic" problem and nutrient poverty yourself. This requires the use of other materials or additional fertilizer and lime to neutralize the acid. Since we are all not chemical laboratory technicians, an optimal composition can hardly be achieved exactly.The criticisms of the environmentalists
It takes about a thousand years for peat to form from plant debris. The peat bog layer grows by only one millimeter a year. In contrast, we humans hold the record when it comes to dismantling. Although the moor is growing, it cannot nearly and promptly compensate for the degradation. As a result, raised bogs are shrinking and irretrievably disappearing.
But why is the moor so important? These are the reasons:
- the bog areas make up about 3% of the earth's surface
- But they store 30% of the earthbound CO2
- that is an important contribution to climate protection
- Moors store water
- they only release it slowly into the groundwater
- this counteracts flooding
- the moor is a valuable habitat
- Plants and animals specialized in it can only exist there
Note: Peat is mined cheaply, especially in Eastern Europe. He has to cover the long way to us in trucks. Along with other environmentally harmful substances, a lot of climate-damaging CO2 gas is emitted.
Peat reduced products
There is now earth on the market that is offered with a reduced proportion of peat. This should also satisfy environmentally conscious buyers and encourage them to buy. Indeed, the proportion of peat is reduced, but the amount of peat it contains is still enormous. Instead of 100% it is "only" 80%. Everyone should decide for themselves whether they consider this reduction sufficient or see the whole thing as a pure marketing move.
What does a substitute have to offer?
Alternative ingredients for potting soil should of course be environmentally friendly and sustainable themselves. Furthermore
Peat-free soil from the trade
It is also available, albeit currently with a modest market share: completely peat-free potting soil. Their composition consists of the following natural materials that make peat superfluous:
- Bark humus
- Fibers made from wood, coconut, Chinese reed or hemp
- with the addition of lava granulate, sand or clay minerals
Note: Coconut palm cultivation areas are far away from us. The long transport route is anything but climate-friendly. Environmentally conscious gardeners also do without potting soil that contains this substance.
Alternatives for peat
Potting soil does not always have to be expensive and time-consuming in the garden center. Anyone can mix a good plant substrate at home. The composition depends on the intended use. However, many recommendations require the addition of peat. However, depending on the function the peat is supposed to fulfill, an alternative material can be used.
- a portion of sand loosens solid soil
- Xylitol or bark mulch are also suitable for this
- Compost also brings in plenty of nutrients
- Grape ester lowers the pH
- alternatively special, acidic compost
- Expanded clay provides water and aerates
In most cases, nutrient-poor potting soil is required for cultivation. This can be achieved by adding perlite and coconut humus.
Tip: Don't just look for peat-free substrate. Other products such as small growing pots can also be made from peat.
Use peat carefully?
Here the recommendation could be to use peat only in exceptional cases and only in small quantities. But given that peat is replaceable, there is no need for it. Of course, we can and may use up peat that has already been purchased. Rhododendrons and azaleas, for example, will benefit from it because they like acidic soil.
