Deciduous azaleas are among the most valuable shrubs that can be grown. Each spring they provide a lavish and brilliant display of flowers. In addition to the well-known favorites, one group, the Knap Hill azaleas, were a big hit with the public.

The Knap Hill azaleas contained the finest of all hybrids and owed their origin to Anthony Waterer, Sr., and his son Anthony Waterer, Jr., who developed them over a period of 50 years at the Knap Hill Nursery in England.

Several American species were used in creating these hybrids. notably Azalea calendulacea and Azalea occidentalis. These were merged with the European Azalea pontica and the Asiatic Azalea mollis and Azalea sinensis to such an extent that the parentage of each Knap Hill azalea could only be a matter of conjecture. They flower in England from early May until the middle of June, reaching the peak of their display toward the end of May. Some had enormous flowers, some medium-size and several are double. The colors range from pure white through yellow and orange, to pink, scarlet and crimson.

Azalea occidentalis and Azalea sinensis are not generally hardy in the eastern portion of the United States. On the other hand, all the other species used as parents at Knap Hill are hardy. I think it is reasonable to expect that at least 80 per cent of the Knap Hill azaleas were able to survive winter temperatures in the area lying between Massachusetts, Ohio and North Carolina. It must be remembered that azaleas dislike hot sun and drought. Moist, well-drained soil and an open situation which is shielded from scorching sun suit them best.

These were ideal plants for a small garden, as they are reasonably tidy and compact in habit. They could grow only in acid soils and did not tolerate lime. A mulch of well-rotted leaves from time to time is all the feeding they required.

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