Purple-stemmed aster grows in wet places: pond margins, marshes, shrub swamps, fens, wet thickets, ditches and moist meadows. It ranges from the edge of the Great Plains to the Atlantic coast and from the Gulf coast of Texas north to southern Ungava Bay in Quebec, and it is native in Quebec. It is a wetland obligate, and its late flowers feed many bees, including specialist mining bees that collect pollen only from asters.
Linnaeus first named the plant Aster puniceus. The species name is Latin for crimson or reddish purple and refers to the colour of the stems. The Icelandic botanists Áskell and Doris Löve later moved it to the genus Symphyotrichum, where most North American asters are now placed. Botanists have named many forms of this variable plant.