Aromatic Aster (Aster ablongifolius) - Perennial with small, fragrant, purple flowers clusters that bloom in late summer until the First Frost. 
 
Growth: Can grow up to 3 feet tall, with a spread of 3 feet.
Light: Full sun in open areas
Soil: prefers dry, lean soils.
Hardiness: Tolerant of heat, pollution, & soil compaction.
Maintenance: Low maintenance & self-seeds.
Benefits: Attracts butterflies. Great for wildlife habitat restoration.