The Alpine Edelweiss (Leontopodium alpinum) is widely distributed at higher elevations throughout the European high mountains (Pyrenees,Alps, Carpathians and Northern Balkans). However, it is well-represented in regions of base-rich soils (on limestone or other base-rich rocks), but absent or subsiding in acidic areas.We tested the growth of L. alpinum in relation to soil pH (isolated in vitro germination on a large range of pH), and under competition (with Nardus stricta L., pot cultivation). The results suggest that, as typical for many ‘basiphilous’ plants, L. alpinum grows well on acidic substrates, although germination rates are lower than under neutral or basic conditions. Competition was confirmed as the main limiting factor that does not allow proper growth or resistance of L. alpinum against Nardus stricta, a strongly competitive species on acidic soils. Accordingly, a species-specific factor, which is the small size and low competitiveness of L. alpinum, is mainly responsible for its absence on acidic substrates. Some physiological intolerance to its germination under acidic conditions may be involved as well.