American Hydrangea Society
Dedicated to the study of the genus, species and cultivars, as well as culture, habits, and hardiness. Event schedule, new introductions, photographs and resources.
Azalea Society of America
Gives information about azaleas, "the royalty of the garden". There are azaleas for almost any growing situation you have, with almost any color, habit and height you desire
Holly Society of America, Inc.
Society for people interested in hollies, including both novices and skilled growers, to exchange information through scientific studies, publications, meetings, visiting holly collections, and other educational activities. Includes information about various species.
International Oleander Society
Dedicated to the promotion of the Oleander in culture, history and lore features articles and membership information.
The American Boxwood Society
Not-for-profit membership organization devoted to the appreciation, scientific understanding, and propagation of the genus Buxus.