Grassland restoration practice in Central Europe: drivers of success across a broad moisture gradient

Ongoing ecosystem degradation and loss demand restoration efforts worldwide. In Central Europe, semi‐natural grasslands are in focus, and better understanding of restoration success and its drivers is needed. For practical projects, systematic screening remains lacking. We compared plant species composition of 41 recipient sites 3–18 years after restoration via plant material transfer with composition of their donor sites. Further, we analyzed establishment of habitat‐typical and endangered species. Spanning a gradient of moisture conditions, sites were located in Germany and Luxembourg. Soil characteristics, biomass productivity, and restoration setup (e.g. previous site state, age) were investigated as potential drivers of success. In dry grasslands, success was highest, likely due to the creation of raw soils at several sites before plant material application. While raw soils generally favored the establishment of endangered species, the resulting low‐productive and dry conditions sometimes posed challenges for mesic grassland restoration. In mesic grasslands, elevated soil pH of some recipient sites further contributed to divergence in species composition compared to donor sites. In alluvial grasslands, high nutrient and productivity levels of recipient sites impeded restoration success. Wet grasslands were successfully restored when soil moisture was sufficient. Across grassland types, species richness decreased with time since restoration, yet the number and cover of habitat‐typical and endangered species remained stable. Introducing typical species in addition to plant material transfer supported restoration. We advocate for large‐scale, systematic investigations of practical grassland restoration projects combined with well‐defined monitoring guidelines across different regions to address this complex challenge in the coming decades.