Dirk Röse

Green compost: a sustainable and high-quality alternative

Alternative constituents

Klasmann-Deilmann takes its responsibility to the environment and society seriously and is regarded as one of the most sustainable companies in the growing media industry. Amongst other things, this is because it began to devote considerable time, effort and funds to the development of alternative substrate constituents at a very early stage. Klasmann-Deilmann began to operate its own composting facilities in 1991. Since then, growing media on a green compost basis have become increasingly popular, especially in the organic horticultural industry.

When Lower Saxony’s peatland protection programme, entered into force in 1981, the Klasmann Werke, as the company was called at that time, began to develop alternative substrate constituents. Emsland district authority organised the separate collection of green waste, providing a valuable resource for the production of substrate composts and creating new business opportunities. In 1991, Klasmann-Deilmann inaugurated its first composting plant in Groß Hesepe producing compost that was suitable for use in growing media. The company meanwhile has two plants which produce substrate compost which is used in its growing media for the professional horticultural sector, while a third plant supplies quality compost for use in potting soils.


Since then, Klasmann-Deilmann has successfully marketed growing media which contain a compost share of between 10 and 30 per cent. The development of high-quality green compost went hand in hand with the company’s own ventures into the organic growing business, which was a completely new market segment at that time. Today, Klasmann-Deilmann is the market leader in the organic growing media market for ecological horticultural businesses. The company’s green compost is sold under the “TerrAktiv” brand and enjoys an excellent reputation with professionals, not least because of the uniquely high quality standards developed by Klasmann-Deilmann over the years. Moreover, Klasmann-Deilmann’s composting facilities are the only ones in Germany to have passed the strict certification process of “Regeling Handels Potgronden” (RHP). Based in the Netherlands, RHP is a European knowledge and quality centre for growing media for professional horticulture and consumers which is highly respected throughout the world.

Firstly, green compost is a valuable natural source of nutrients for plant growth. Secondly, it has high microbial activity, strengthens plant vitality and protects them against root disease. Green compost is therefore ecological plant protection which can reduce the need for chemical protection products, an aspect which has meanwhile made it an increasingly attractive option for conventional ornamental plant businesses and tree nurseries. There is scientific evidence of the extremely positive effects that an addition of only 10 per cent TerrAktiv green compost has on the health of sensitive container plants. One of the findings of a study by the French ASTREHOR Loire-Bretagne research centre proved that plants grown in media containing TerrAktiv green compost are healthier and more vigorous. Developing compost as a plant strengthener will be a focal point of our work in the coming years. Several tree nurseries in the Weser-Ems region are currently being supplied with container substrates that include a share of compost to strengthen their plants.