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.
Botanists have decided for the time being that there is only one species, namely the British polifolia, a dwarf evergreen shrub about 1 ft. high, found wild in British and Irish peat bogs. It has pinky-white drooping flowers tipped with red from May to August. There are several varieties, such as rosmarinifolia, canadensis, rubra, angustifolia, etc. Propagation is by seeds or layers. Other plants known to nurserymen and gardeners under the name of Andromeda are Pieris floribunda, 2-6 ft., with pure-white flowers in April and May; P. japonica, 3 ft., white, with the varieties elegantis-sima and variegata. The plants also now known under the names of Lyonia, Cassandra, Leucothoe, and Oxydendron are still referred to as Andromedas by many in the trade. The lovely pure-white Zenobia speci-osa, and its variety pulverulenta, was formerly known as Andromeda deal-bata, owing to the whitish under surface of the leaves.