Symphyotrichum firmum is a perennial herbaceous plant that can reach heights of 2 meters (6+1⁄2 feet).

The leaves are alternate, up to 15 centimeters (6 inches) long and 3 cm (1+1⁄5 in) wide, and clasp the stem.

[3] In the United States, it occurs in the Midwest, some parts of the Northeast, and in the Appalachian Mountains south to Georgia.

[6] Symphyotrichum firmum grows in moist and sunny areas such as fens and wet prairies.

[a][7] As of December 2021[update], NatureServe listed Symphyotrichum firmum as Secure (G5) worldwide, Vulnerable (S3) in Quebec, and Presumed Extirpated (SX) in New Jersey.