Suitability of a perennial biogas flower mixture for cropping on sandy soils in Brandenburg

Abstract

Due to their broad site adaptation perennial wildflower mixtures for biogas production could be an alternative to maize cropping. If they provide high biomass yield from vital growing species and promote biodiversity even in low yielding regions. Field trails were established in order to test the ability of a perennial flower mixture on sandy soils to promote species rich vegetation. The wild flower mixture “BG 70” was sown at two sites in Brandenburg. This mixture contains 23 species and was especially developed for biogas production. From 2015 until 2017, new plots were sown with the mixture every year. Wild flowers and weed species were counted at several dates. The diversity of the wild flower mixtures decreased over the years. In the second year after sowing, the perennial wild flower species Centaurea nigra and Artemisia vulgaris dominated. The number of individual wild flower plants was low at the beginning and declined further. Surprisingly, the weed density also dropped enormously over the years. In the late summer months (August and September) the wild species complement the food supply for animals to the natural grown vegetation.