Alfred S. Martin, Mountaintop, Pa.
Guest editor, Gordon Jones, and his associates of the Brooklyn Botanical Garden are to be congratulated for the Summer 1971 Plants and Gardens Quarterly devoted to Rhododendrons and Their Relatives. The twenty-four contributors to this extremely useful pamphlet comprise as distinguished a group of experts that could be assembled.
All groups of enthusiasts from beginners to experts and from amateurs to professionals will find a great many things of interest in the articles of this volume. Among the most interesting features are the sections on favorite rhododendrons and azaleas by region. While there is bound to be some controversy in lists of this nature, the individual contributors for the ten sections of the United States covered have brought together information which is of great value to regional enthusiasts.
Dr. Gustav A. L. Mehlquist's contribution on "Cold Hardiness in Rhododendrons," Alfred Fordham' s "Mountain Laurel and Its Propagation"; and Dr. Henry T. Skinner's "America's Native Azaleas" were among the high points of interest to me. Dr. Mehlquist always brings a clear and incisive understanding of complicated matters in easy to read fashion. Alfred Fordham also tends to make relatively difficult propagation problems seem extremely simple. His work on the propagation of difficult plants has always been outstanding. I always felt that the use of native azaleas in our gardens has been neglected and Dr. Skinner's excellent treatment of this subject should inspire many gardeners to further use of these extremely valuable ornamentals. With the exception of R. serrulatum and R. oblongifolium, all of the seventeen native species have been quite happy in my own garden near Philadelphia.
Harold Epstein, Joseph A. Witt and Hazel and Don Smith all have interesting contributions on companion plants for rhododendrons and azaleas. These beautiful plants are too often overlooked by both beginners and avid collectors. Remarkable interest and variety can be brought to any gardens by judicious use of these companion plants which heighten the effectiveness of rhododendron and azalea plantings. Pamela Harper offers a wealth of information on the use, selection and culture of heaths and heathers. Regional growers will largely have to experiment with this group of plants to determine the usefulness in their individual areas. Certainly some of them can be grown in almost any section of the country. One of the great features of all in this group or articles is that information is included as to where the plants can be obtained.
There are a few articles of more regional than national interest but who could be uninterested in Jock Brydon's informative treatment of Malaysian Rhododendrons or the Madrona and Manzanitas so ably covered by Joseph Witt and Lee Lenz. Practical propagation and general culture are ably covered by Syd Burns and Harvey Gray. One of the interesting things to me has always been the fact that extremely precise directions are usually given for the size, shape and contents of the hole in which the plant has to be placed but seldom is anything said about what should be done to the root ball of the plant. In view of the rapid growth in popularity and distribution of container plants and the importation of plants from areas in which plants are grown in peat or sawdust, this can be a subject of great concern. Without proper treatment, one can find several years later that the root systems have not taken any advantage of your laborious hole work and the root ball is still confined to the shape of the container, or has not broken out of the original root ball.
In brief, from David Leach's usual excellent general opening article on the Genus to Gordon Jones' closing notes on Books for Further Reading, Rhododendrons and Their Relatives is a valuable and handy publication to have around. Copies can be obtained for 51.50 from the Brooklyn Botanic Garden, 100 Washington Avenue, Brooklyn, New York 11255 by requesting Manual #66, "Rhododendrons and Their Relatives."