'Purple Dome' aster is a tried-and-true fall-blooming perennial and perhaps the best of the New England asters (Symphyotrichum novae-angliae) thanks to its strong upright habit and incredible mass of flowers. While other varieties tend to eventually flop, Purple Dome keeps its compact, sturdy-stemmed shape all through summer and fall. This fall flower also offers late-season food for bees and butterflies.
Common name: 'Purple Dome' New England aster
Botanical name:Symphyotrichum novae-angliae ‘Purple Dome’
Exposure: Full sun to part sun
Season: Fall, for flowers
Flowers: Purple rays surround a yellow eye from early fall until frost. The flowers completely cover the plant for a long period of time.
Size and habit: 'Purple Dome' aster grows 18 inches tall and up to 36 inches wide, with a mounded shape.
Origins: The species Symphyotrichum novae-angliae is native to open woods, meadows and stream banks of the eastern United States. 'Purple Dome' aster was introduced by the Mt. Cuba Center in Delaware after being discovered growing along a roadside near Allentown, Pa., by Robert Seip.
Related: "Hardy Perennials That Bloom in the Fall" (all introduced from Mt. Cuba Center)
How to grow 'Purple Dome' aster: Site it in full sun for the best performance, although it will grow and flower in part sun. Good drainage is essential and regular moisture is preferred, though this aster can adapt to less-than-ideal conditions. Consistent watering is especially important in its first season as it is getting established. Thereafter it can take short stints of drought. Remove old stems and leaves in late winter to make room for growth to commence in spring. 'Purple Dome' aster can be divided in the spring. USDA Zones 4–8.
Image by Drew Avery/CC BY 2.0