The above-ground growth (stems and foliage) of Jerusalem artichoke (Helianthus tuberosus L.) was studied in field experiments in Sweden during 1981 to 1983, in order to investigate the possibility of producing biogas from biomass. Dry matter yields of three varieties were determined at four different harvesting times. The yields varied between 7 and 16 tons of dry matter per hectare. Anaerobic digestion experiments showed that fresh and ensiled above-ground parts of the plant could produce 480–680 litres biogas per kg organic material. The chemical composition of the plant material was determined before and after digestion.