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Widespread changes in arctic and boreal Normalized Difference Vegetation Index (NDVI) values captured by satellite platforms indicate that northern ecosystems are experiencing rapid ecological change in response to climate warming. Increasing temperatures and altered hydrology are driving shifts in ecosystem biophysical properties that, observed by satellites, manifest as long‐term changes in regionalNDVI. In an effort to examine the underlying ecological drivers of these changes, we used field‐scale remote sensing ofNDVIto track peatland vegetation in experiments that manipulated hydrology, temperature, and carbon dioxide (CO₂) levels. In addition toNDVI, we measured percent cover by species and leaf area index (LAI). We monitored two peatland types broadly representative of the boreal region. One site was a rich fen located near Fairbanks, Alaska, at the Alaska Peatland Experiment (APEX), and the second site was a nutrient‐poor bog located in Northern Minnesota within the Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment. We found thatNDVIdecreased with long‐term reductions in soil moisture at theAPEXsite, coincident with a decrease in photosynthetic leaf area and the relative abundance of sedges. We observed increasingNDVIwith elevated temperature at theSPRUCEsite, associated with an increase in the relative abundance of shrubs and a decrease in forb cover. Warming treatments at theSPRUCEsite also led to increases in theLAIof the shrub layer. We found no strong effects of elevatedCO₂on community composition. Our findings support recent studies suggesting that changes inNDVIobserved from satellite platforms may be the result of changes in community composition and ecosystem structure in response to climate warming.