Perennial Salt Marsh Aster (Symphyotrichum tenuifolium)

A perennial aster of saltmarsh and freshwater wetlands, 

to 3 ft in bloom. Spreading by rhizomes, it can form dense clumps

that are attractive when in bloom, despite being lankier

and having relatively fewer flowers than most other native asters.

Grows in wet soil and shallow water, and tolerates brackish water.  

Flowers best in full sun. Ideal in a shallow water feature. Not tolerant

of dry soil.