Aster (Symphyotrichum) ericoides f. prostratum ‘Snow Flurry’ AGM

Heath Aster Asteraceae

Symphyotrichum ericoides var. prostratum ‘Snow Flurry’ is one of the most useful of the late-flowering heath asters, forming a remarkably low, spreading mat of wiry, arching stems rather than the usual upright tower associated with Michaelmas daisies. Tiny, narrow, dark-green leaves clothe the stems, which in late autumn become smothered in small white, yellow-centred flowers, producing the effect of a miniature snowstorm across the ground. The RHS describes it as stiffly prostrate and mat-forming, with a spread of up to 1 m. 

The species is native to North America, and S. ericoides takes its specific name from its heath-like foliage, the narrow, rigid leaves giving the plant a distinctly Erica-ish appearance. ‘Snow Flurry’ takes that already rather wiry architecture and sends it sideways, making it particularly good scrambling over rocks, walls or the front of a border. Missouri Botanical Garden records it at only around 10–15 cm tall but capable of spreading to approximately 1.2 m. 

Its history in Britain is rather nice. Beth Chatto brought ‘Snow Flurry’ from the USA to Britain in the 1980s, and it subsequently became valued as an unusually low-growing late-season aster. It was also included in the Chicago Botanic Garden’s extensive 2015 aster evaluation, where its low mounding habit was considered one of its distinguishing qualities. 

The nomenclature is slightly untidy, as one might expect from a plant that spent much of its horticultural life being called an Aster. It has appeared as _Aster ericoides f. prostratus ‘Snow Flurry’, Aster ‘Snow Flurry’ and several other combinations. The RHS currently lists _Symphyotrichum ericoides var. prostratum ‘Snow Flurry’, while also recording Symphyotrichum ericoides f. prostratum ‘Snow Flurry’ as a synonym. 

An excellent plant for rock gardens, gravel gardens, the front of borders and naturalistic planting, particularly where a low-growing plant is wanted to provide a final burst of flowers after most of the border has gone to sleep. It is also an RHS Award of Garden Merit plant and is rated H7, so there is little excuse for blaming the weather if it fails to survive a British winter. 

Cultivation: Full sun in moderately fertile, well-drained soil. It is particularly effective allowed to scramble over rocks or the edge of a raised bed. Cut back after flowering in late autumn or early spring; division is best carried out in spring. 

Height: 10–20 cm
Spread: 90–120 cm
Flowering period: September–November
Position: Full sun
Soil: Well-drained, moderately fertile; tolerant of chalk, loam and sand
Hardiness: H7
Family: Asteraceae
Common name: Heath aster ‘Snow Flurry’