Saxifraga oppositifolia, a widespread circum‐arctic and alpine plant species, was exposed to increased temperature at three ITEX sites of different latitudes: Val Bercla in the Swiss Alps (46°N), Latnjajaure in mid‐alpine Northern Sweden (68°N), and Alexandra Fjord, Ellesmere Island (79°N) in the Canadian High Arctic. Phenology, growth, and reproduction were monitored for 2 or 3 consecutive years. Increased temperature had lit...