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.
This genus has a few good rock plants, the best being alpina, 6 in., purple; glabella, 3 in., lilac purple; and grandiflora, 9 in., purple. They flourish in ordinary soil, and are increased by seeds and division.
 
Continue to: