[4] Symphyotrichum greatae is a colonizing perennial herb growing from a long rhizome.

It produces upright to erect stems usually 50 to 120 centimeters (1+3⁄4 to 4 feet) tall.

The leaves are mostly oval in shape and pointed, the ones at the base up to 15 centimeters (6 inches) long.

[3] The inflorescence is an open array of flower heads amidst leaflike bracts.

[3] Symphyotrichum greatae is endemic to the San Gabriel Mountains of Southern California, where it grows in damp areas in the canyons of the southern slopes above the Los Angeles Basin.