During the last few years, renewable energy systems have been becoming increasingly important. In particular, biogas production from agricultural raw material has gained importance in Austria. Due to the rising number of organic farms and energy prices, the use of plants for biogas production becomes more and more interesting for organic crop growing. The main objective of this thesis is to assess the dry matter yields of various crops fertilised with biogas slurry for one year. In addition to the dry matter yield, the dry matter content of the harvested crops plays an important role in biogas production. Field trials of different crops show the potential of dry matter yields. In this respect, a comparison of the yields of red clover, red clover grass, maize after a winter catch grop, sunflowers after a winter catch crop, maize after green rye and maize after a vetch-rye mixture was conducted in Lambach (Upper Austria) with a focus on two different levels of fertilization (0 kg N, limitation of liquid manure according to the ÖPUL directive). The results show that especially the use of maize as second crop after vetch-rye mixture with slurry fertilization reached the highest dry matter yields in organic farming. Annually, 22.1 tonnes of dry matter per hectare can be achieved. Red clover gained with three harvests up to 11.5 tons of dry matter per hectare. Sunflowers produced up to 14.1 tonnes of dry matter per hectare under appropriate weather conditions and slurry fertilization. Resumingly, the growing crop of red clover, red clover-grass and the yields of rye und vetch-rye mixture are suitable for biogas production in organic farming. Furthermore, biogas slurry can be used to increase market crop yields of maize and cereals. Nevertheless, the biogas production in organic farming must not compete with food production. The basic idea of sustainability and balanced crop rotation is indispensible for organic farming.