Symphyotrichum laeve
Big cone shaped clusters of single violet-blue flowers with golden yellow centers, an inch or more across, appear on the top half of a vase shaped clump. Perfectly clean foliage. Tolerant of a variety of soil types and moisture levels. Even at 4' it needs no staking in full sun.
Habitat
Aster laevis is found open dry places from Maine to Georgia, west to New Mexico and British Columbia.