swamp aster

Also known as Purplestem Aster, Red-stalk Aster, Early Purple Aster, Cocash

Swamp asters thrive in saturated soils along marsh edges, fens, and stream banks, standing out in late summer and autumn with brilliant displays of pale violet to blue ray florets. Distinctive stout, bristly reddish-purple stems support branched floral sprays that act as critical late-season nectar stations for migrating butterflies and prepping bumblebees. Stems can form robust, clonal colonies via creeping rhizomes, stabilizing wet ditch banks and saturated meadows against seasonal flooding.