This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Ornamental evergreen shrubs from North America, of which the best-known kinds are angtustifolia, the Sheep Laurel, 2-3 ft. high, with oblong leaves and corymbs of purple or crimson bell-shaped flowers. There are a few varieties: glauca has grey-green leaves and lilac-purple flowers in April; and latifolia, the Calico Bush, 3-10 ft. high, with broader leaves and masses of rose to white flowers. All kinds flourish in peaty soil and in loam with plenty of leaf mould, and are raised from seeds and layers.