Introduction: Knowledge about the regeneration ecology of silver birch (Betula pendula Roth), a key species of early woodland development stages, is fundamentally important to establish strategies for developing near-natural woodlands in post-mining landscapes. On 119 plots covering three former open cast lignite mining areas, we studied the effects of different microhabitats for germination and early establishment leading to successful birch colonization. Methods: We introduced seeds (ca. 50,000 germinable seeds per m²) onto various substrate and competition treatments. Results and Discussion: Despite a standardized introduction of a high number of birch seeds, we found a high variability in the regeneration ability of silver birch. Early birch establishment was observed only on one quarter of the groundwater-distant sites with 1 to 115 individuals per m2. Suitable establishment conditions were lacking on most sites. We observed seedlings in high densities on all sites influenced by groundwater (up to 4,800 individuals per m²). On groundwater-distant sites, we noticed highly dynamic patterns of germination, mortality and re-germination due to alternating wet and dry periods. Longer precipitation periods were obviously related to higher seedling establishment. On a very small part of cohesive, groundwater-distant sites, bioturbation by earthworms strongly decreased seedling survival in the second year. The volumetric water content and the percentage of vegetation-free patches were found to be important parameters affecting the regeneration ecology on nutrient-poor sites. Also, the percentage of clay content, the height of litter cover or hay mulch layer, and soil pH significantly affected the number of individuals on groundwater-distant sites. The amount of clay content and the height of litter cover or hay mulch layer were crucial for the soil water retention of the young dump raw soils, where humus content is generally nearly absent. Conclusions: In the course of restoration on former lignite mining areas assisted measures promoting near-natural woodland development should vary due to the site-dependent variability of the establishment success of silver birch: (1) Assisted measures are not necessary if seed bed conditions are suitable, no danger of erosion exists and diaspore sources are available. Suitable seed bed conditions exist on sites influenced by groundwater as well as groundwater-distant, vegetation-free sites with higher clay content (≥ 10%). To minimize the dislocation of diaspores, the sites should feature a high surface roughness. (2) Due to danger of erosion as well as unsuitable seed bed conditions on groundwater-distant sites (clay content < 10%, low surface roughness), the application of a hay mulch layer can promote early birch establishment. In case of lacking diaspore sources, silver birch seeds should be introduced additionally. (3) In the case of advanced herb layer development, open soil should be created in certain places. However, in priority nature conservation areas, assisted measures to promote woodland development should be dispensed with.