Elevation gradients provide ideal scenarios to study plant responses to environmental factors and to global warming. Physiological and morphological traits, growth, and reproduction in bilberry were investigated at 6 elevations along an elevation gradient from 350 to 2000 m asl. Chlorophyll content and growth increased with elevation, reaching a maximum at 950 m, and then decreased, with both variables being negatively influenced by high soil pH. By contrast, after removing the positive effect of tree canopy cover, the efficiency of photosynthesis did not show differences between elevations. The number of stomata per area increased with elevation, while leaf area reached maximum values at 950 m. Regarding reproductive traits, densities of flowers and fruits were not affected by elevation, and fruit set, seed set, and seed viability only varied between localities within elevation. Moreover, flower production was negatively correlated with soil pH. Reproductive success was not limited by pollen quantity at any of the elevations. However, elevation affected number of ovules, number of mature seeds per fruit, and fruit dry weight; these variables reached their highest values at around 1700 m. These results show that, while bilberry exhibited the most favourable vegetative performance at mid elevations, maximum reproductive output was observed at higher elevations.