Beavers have long been recognized as habitants of peatlands, with their range extending over 95% of the peatlands in Canada. The hydrological impacts of beaver dams are known to alter plant community composition. While the first response of vegetation to a change in abiotic conditions is usually a change in plant phenology, i.e. the timing of green up and senescence, little is known of how beaver dams affect plant phenological patterns. Here, we extracted the green chromatic coordinates from digital repeat RBG photography at a fen in the Canadian Rocky Mountains to determine if beaver damming affected the length of the growing season and the timing and duration of peak plant growth. Photos were acquired weekly between May and September 2022 with an unpiloted aerial vehicle in areas of the peatland (active beaver, abandoned beaver, and no beaver) and along a 200 m transect extending outward from a pond. We found that areas of the peatland near active beaver ponds had higher greenness than areas of the peatland with no beaver ponds or abandoned beaver ponds. As well, greenness declined with increasing distance from beaver ponds. The study has implications for understanding how beavers change peatland ecosystem function and carbon-climate feedbacks.