The effects of climate change on plant-pollinator communities have been studied primarily by looking at how flowering phenology is changing, and usually just by recording first flowering dates. Few studies have looked at the whole flowering period. We have found in a 40-year study of 60 species that 27% of wildflowers in the Colorado Rocky Mountains are not changing first flowering dates but are changing the timing of peak and end of flowering, and in 56% the changes in first flowering are not representative of the direction and magnitude of changes in peak and last dates. In only 17% of species are the three measures of first, peak, and last flowering changing in the same way. These changes are resulting in new patterns of co-flowering, which may have important consequences for pollinators and their interactions with the food plants. Seasonal patterns of flower abundance are also changing, with a mid-season low point developing between earlier and later peaks. Pollinators are also responding to climate change. Migratory hummingbirds and overwintering bumble bees are changing their phenologies relative to their food plants. Experimental manipulation of snowpack sometimes resulted in changes to pollen limitation and reproduction in an early-flowering species.