Selection against early flowering in geothermally heated soils is associated with pollen but not prey availability in a carnivorous plant

This data set includes data on flowering phenology, rosette diameters and fitness of the perennial herb Pinguicula vulgaris, as well as data on soil temperature and experimental treatment applied. The data was collected during the summer of 2020 in 287 plant individuals located in a sub-arctic geothermal area in Ölfus municipality in SW-Iceland, Hengill (64°03’N; 21°18’W, ~360 m.a.s.l.).