A hybrid of A. amellus x A thomsonii this perennial aster from Switzerland combines the large flowers of A. amellus and the long bloom time of A. thompsonii. The leaves are dark green and hairy while the flowers are lavender-blue with yellow centers, up to three inches across, and borne in masses for about eight weeks from mid summer to fall. Unlike many other asters, the foliage is mildew resistant throughout the season even in the humid South. “Wonder of Staffa’ is a very similar cultivar and is said to have lighter blue flowers and be more prone to flop.
Type: Herbaceous perennial
Bloom: Lavender blue flowers with yellow centers, 2-3” across, bloom for about eight weeks from mid summer to fall
Size: 2-3’ H x 1-1.5’ W
Light: Full sun but tolerates some shade.
Soil: Average, medium moist, well-drained, neutral to slightly alkaline; wet soils in winter cause root rot.
Hardiness: Zones 5-8 (5 and 6 with protection)
Care: Fertilize and mulch in spring; water in drought; pinch back in spring to reduce height, promote bushiness, and delay bloom.
Pests and Diseases: None of significance
Propagation: Division in fall or spring; softwood cuttings from mid to late spring
Companion plants: Black eyed Susan (Rudbeckia fulgida var. sullivantii ‘Goldsturm’), golden rod ‘Fireworks’, Joe Pye weed ‘Little Joe’