Appearance
It grows to be about 6-12 inches . The bloom color may be pink, violet/lavender, dark purple/black, or white/near white and may bloom in late spring/early summer or, occasionally, midsummer. In the UK this plant has gained the Royal Horticultural Society's Award of Garden Merit.Status
In Canadian provinces, towards eastern North America, the species is critically imperiled. However, in both Canadian provinces and US states, at north-western and southern parts, the species is apparently secure.Habitat
It does better in generally cooler climates. Usually it is adapted to clay, silt, loam, silty clay, sandy clay, clay loam, silt loam, sandy loam, silty clay loam and sandy clay loam soils, and prefers low fertility. The plant can tolerate only a minimum temperature of -28°C / -18.4F after the occurrence of cell damage. It can survive medium heat of fire and requires at least 90 frost free days for proper growth. It is herbaceous and attractive to bees, butterflies, and birds.References:
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