Michaelmas daisy

Symphyotrichum novi-belgii is a herbaceous perennial of the daisy family growing 60-150 cm tall from spreading rhizomes. Stems are erect, glabrous or finely pubescent in lines, often branching only in the inflorescence and frequently flushed with purple. Leaves are alternate, lanceolate to narrowly elliptic, 5-15 cm long and 1-3 cm wide, smooth or slightly clasping at the base, with entire to remotely serrate margins; upper leaves are reduced and bract-like. The inflorescence is a leafy, open panicle of numerous flat-topped capitula each 2-4 cm across; ray florets are 20-40, narrow, and bright violet-blue, lavender, or occasionally pink to white, surrounding a central disc of yellow tubular florets that turn reddish-purple with age. Involucral bracts are imbricate in 3-5 series, narrow, with appressed green tips. Native to moist meadows, marshes, and shores of eastern North America, it flowers from August into October.