The climate impact of the now widely used peat as a substrate is very high. Peat consists of plant material (mainly sphagnum moss) that has been converted into peat through humification. Peat formation is a slow process. The peat landscape only grows by approximately 1 millimeter per year. By excavating fossil peat and using it as a substrate, all this carbon is returned to the atmosphere in the form of CO2 and the peat ecosystem and biodiversity are affected. Peat excavation mainly takes place in the Baltic States and Germany.

“We are the only ones who get the moss from New Zealand. I would also like to have it closer, but there is no moss of the same quality available ”. 

Wubbo Wind, BesGrow. The Netherlands

The Dutch substrate sector produces 4.7 million m3 of potting soil worth EUR 350 million per year. It is estimated that one third of this is used in professional horticulture, one third by consumers and one third is exported. Although there is still enough peat available, this sector is coming under increasing social pressure, with the result that there is a growing demand for more sustainable substrate alternatives.

In 2013, the Responsibly Produced Peat (RPP) quality mark was established to encourage certification of responsible peat extraction. This is a collaboration of the European Peat and Growing Media Association, International Peat Society, the Dutch Association of Potting Soil and Substrate Companies, the German Association for the Garden Industry. Only degraded systems can be certified. In addition, there must be good management with regard to peat extraction and how the peat area is left after extraction. In addition, this quality mark seeks alternative high-quality growth media in the long term lxxv

In addition to making peat excavation more sustainable, the Dutch potting soil industry is actively looking for alternatives to peat. Various alternatives such as coconut fibers lxxvii, wood fibers, biochar, compost, cane chips and mushroom manure lxxviii are already being used. It must be investigated to what extent these alternatives meet all physical, chemical, biological, but also economic conditions and to outweigh the environmental effects of the excavation of peat. Many of these alternatives have drawbacks. Peat moss appears to be one of the few potentially suitable alternatives.

Peat moss is not yet a well-known alternative in the potting soil industry, but is used on a very small scale in the Dutch organic substrate market. Although accurate statistics are lacking, market parties indicate that this market segment is growing. The Bio-Kultura company, which has an organic substrate market, now has 9 years of experience in the processing of peat moss. About 20% of the substrate produced by Bio-Kultura consists of peat moss.

“Yes, we are interested and send us the letter of intent. On the one hand, the growth quality and the available quantity are important. Stability is also important ”. 

Ben Scheers, Pokon Naturado

If we were to calculate in a scenario what implications the processing of 20% peat moss would have in the entire Dutch consumer potting soil (1.5 million m3), this would mean a demand for 300,000 m3 of fresh peat moss. This corresponds to a cultivation area of 1500 hectares.

Since fossil peat mainly comes from Poland and the Baltic states, it must be transported over long distances. Since peat has a low density, its transport is expensive and the only profitable way of transporting it is on big ships that would otherwise go back empty from the Baltics to the west. The increase in fuel prices and increased unrest following the war in Ukraine make this mode of transport more unreliable, increasing the demand for a locally produced growing medium.

An exploratory study has been carried out to estimate the potential costs and benefits of the cultivation of peat moss. Before making this calculation, it should be noted that this crop is not (yet) commercially grown in the Netherlands and that such estimates are difficult. In order to get an idea of ​​the market opportunities, several assumptions are necessary and are only possible by making the best possible estimate of the potential returns from the various applications on the basis of market prices of comparable raw materials. For each application, a substantiation of the figures is provided and it is always indicated which assumptions have been made for this. The economic analysis, per application option, orchid substrate, hobby pot soil and decoration material, is the first to describe an estimate of the costs to be made for furnishing and machinery. From these data, an estimate of the exploitation costs per hectare of cultivated product has been made based on the expected scale size. Subsequently, the potential benefits were estimated. These data lead to a balance with potential costs and benefits and a result. The calculation is based on large-scale cultivation of at least 250 hectares.

Potential yields of peat moss as orchid substrate

For an estimate of volumes per hectare, limited reference numbers are available because peat moss is not grown commercially in the world, but is collected from the wild. EMA-Universität Greifswald has been researching the cultivation of peat moss for over 10 years and they harvest an average yield of 2.5 tons of dried peat moss per hectare on trial fields in Hankhausen. 

• Orchid substrate is sold for an average of € 10 per kg of dried peat moss. Companies like Besgrow import dried and sterilized peat moss from New Zealand (Sphagnum cristatum) and Chile (Sphagnum subnitens) and sell it for prices of EUR 14 and EUR 7-8 respectively (Chilean peat moss quality is inferior). 

• After the harvest, another processing step must take place to make the material weed and disease free1. Costs per ton of dried material: € 400 

• Peat moss must be dried at € 1.50 per kg of dried material and packed in bales. These drying costs are significantly higher than, for example, azolla because the volume is lower and a different drying technique will therefore be used.

Potential yields of peat moss as hobby growing substrate/potting material

• Prices of € 39 per m3 apply in the processing of organic potting soil (1). 

• After the harvest, another processing step must take place to make the material weed and disease free1. Costs per cubic meter: € 5. 

• Sphagnum moss must be dried again (not completely dried, as with orchid substrate). Cost per m³: € 3.

Set-up costs

Investments € 40,500 per hectare + machine of € 20,000 with a total depreciation of € 3,608 per hectare per year

• An estimate of costs, including plant material, is based on € 20,000 per hectare with a depreciation of 10 years. That is € 20,000 / 15 years = € 1,333 per year per hectare. The price of € 20,000 is based on large-scale cultivation of at least 250 hectares. The costs for starting material are currently very high, approximately € 750 per m3 (1). The reason this is so expensive is because starting material is scarce and because peat moss mainly grows in protected areas, where harvesting is not allowed just like that. Starting material costs are currently estimated at EUR 60,000 per hectare. With large-scale cultivation, the cost price of the starting material will be significantly lower, so that this calculation is based on € 20,000. 

• Depending on the area, investments in the construction of dikes, clearing the grass, etc. are estimated at € 15,000 per hectare with a depreciation period of 11 yearslxxxi = € 1,363 per year per hectare. 

• In addition, costs for water management are highly dependent on the system in which cultivation takes place. A simple irrigation system could cost € 10,000 per hectare. These costs decrease per hectare as the peat must cultivation area increases1. In this calculation we assume an irrigation system of € 5,000. per hectare with a depreciation period of 7 yearslxxxii = € 714 per year per hectare. 

• Purchase of grab for harvesting machine: € 20,000 with a depreciation of 7 years = € 5 per hectare, based on 60 hectares of cultivation per farmer. 

• Planting costs for the 1st year: € 500 per hectare with a depreciation of 15 years = € 33 per hectare. 

• During the first 2 years, the farmer has hardly any harvest because peat moss needs time to grow. These start-up costs amount to € 2,400 (2 X the operating costs) are depreciated over 15 years = € 160 per year. 

• The depreciation periods used by the tax authorities (National Agricultural Standard 2015) have been used

Operating costs

• € 5,108 

• Depreciation of the installation costs: € 3,608 per hectare 

• The fixed costs, consisting of depreciation of land, buildings, inventory and machines, are € 700 per hectare. These costs include a lease price of € 360. -lxxxiii (source http://www.boerderij.nl/Home/grondmarkt/Grondprijs/?gebied=2706). 

• The cultivation costs, including petrol and maintenance of machines and irrigation system are € 200 per hectare. 

• Wages are derived from work and are determined from revenues minus costs. 

• Transport and storage: € 500 per hectare. 

• Overhead (office, administration costs, etc.) € 100 per hectare. 

• All work is carried out by the farmer himself.

Guarantee of quality and uniformity

For the substrate applications, the quality of the sphagnum moss is important and that the medium is weed-free and contains no pests or diseases. Peat moss has the desired properties such as structure, structure stability and water retention capacity and airiness. Important factors are the acidity, buffer capacity, nutrient content and the organic matter content. However, different types of Sphagnum have different properties. Research in the pilot will have to show which species and cultivation method is best suited for orchid substrate or organic hobby potting soil. When peat moss meets the RHP certification requirements, it can facilitate entry to the substrate market.

Available starting material 

Starting material is currently expensive. Investments will have to be made in starting material to reduce the costs of peat cultivation.

• Experiment with different types of Sphagnum. Look for the optimal varieties for different applications. Optimize yield, and suitability herein. 

• Optimize together with market parties. In order to produce suitable substrates, it is necessary to coordinate this with market parties. In The Netherlands Bio-Kultura is a strong partner for this, and Pokon-Naturado and orchid growers.  

• Start with the marketing of peat moss as decoration material. Sphagnum moss as a decoration material has excellent yields, but the market is small.  

• Exchange knowledge and experience with the University of Greifswald. Years of research has been done here into the cultivation and processing of sphagnum.  

• For The Netherlands; Use the IPV as a breeding ground for peat moss starting material. Sphagnum moss starting material is expensive at the moment. In order to make this cultivation profitable in the long term, it is important that sufficient high-quality starting material is available. The IPV offers an excellent opportunity to initiate this.  

• Communicate the qualities of peat moss. Discussions showed that peat moss was not known to many market parties for its substrate properties. There was much doubt. Consumers are not aware.  

• Set up (help) campaign. Experience from, among others, the United Kingdom shows that a large proportion of consumers are willing to pay an additional price for sustainable (peat-free) potting soil. Setting up or helping to set up a campaign to inform consumers and citizens about the current unsustainable peat excavation and offering a sustainable alternative can make a good contribution.

For farmers interested in growing organic mushrooms on substrate from paludiculture, it will be necessary to know about the prerequisites set by different organic standards. Furthermore, these farmers need to know about the characteristics of innovative growing materials in comparison to the dominating turf-based products, where to source them, if there are sufficient quantities and how expensive this will be or if additional costs could be covered by environmental payments. Yet, farmers need information on possible supply chains as well as requirements of processors and practical advice on managing rewetted raised peat bogs.