[8] The species grows primarily in coastal salt marshes, although in the Ozarks it occurs as a non-marine weedy variety.

[9] Symphyotrichum subulatum is an annual forb that possesses a single erect stem that can reach up to 1 meter (3 feet 3 inches) in height.

parviflorum (Nees) S.D.Sundb., as of December 2021[update], are accepted at the species level by POWO as Symphyotrichum divaricatum (Nutt.)

[14] Symphyotrichum subulatum is a terrestrial species that will typically grow among grasses of any kind.

[11] According to the Lady Bird Johnson Wildflower Center, eastern annual saltmarsh aster can be planted to attract butterflies and has value for native bees.