Symphyotrichum tradescantii (formerly Aster tradescantii) is a species of flowering plant in the family Asteraceae native to northeastern North America. Common names include Tradescant's aster and shore aster.
Symphyotrichum tradescantii is a perennial, herbaceous plant that may reach tall. Its flowers have white ray florets and pale yellow to purple disk florets.
Symphyotrichum tradescantii is native to northeastern North America in Canada (New Brunswick, Newfoundland, Nova Scotia, and Québec) and the United States (Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont).
It is an introduced species in the Czech Republic, Slovakia, Slovenia, and Croatia.
S. tradescantii is found in wet and rocky habitats such as shores, streams, and freshwater estuaries.