This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
A charming North American rock plant, 3-6 in. high, having roundish leaves becoming purple red in winter, and with funnel-shaped flowers in March and April, white shading into rose. The Japanese S. uniflora has soft pink flowers. Both kinds like sandy peat and loam, and are increased by careful division and seeds.