QBARS - v25n1 Survey of Hybrids & Species in the Atlanta Area

A Survey of Rhododendron Hybrids and Species
in the Atlanta Metropolitan Area
Robert L. Schwind

This survey was undertaken at the request of the President of the Azalea Chapter of the American Rhododendron Society and is the first phase of a continuing program to test the suitability of rhododendron hybrids and species in the Atlanta metropolitan area.

The Atlanta area is about 1000 feet above sea level, lies just south of the 34th parallel, and averages annually about 50 inches of rainfall spread rather evenly throughout the seasons of the year. The winters are mild with temperatures occasionally dropping below 5 degrees for a few nights; the summers are warm with temperatures frequently exceeding 90 degrees. Generally the humidity is relatively high, but not often oppressive. The Atlanta area experiences a high intensity of sunlight ameliorated by a heavy cover of pines and oaks. The numerous forests in and around the metropolitan area harbor various species of native azaleas and indigenous colonies of R. maximum and R. minus .

The rating program is designed to compensate for the inadequacies of ratings and hardiness classifications obtained from the Northwest, the source of much of materials. With few exceptions local nurserymen are also of little help and continue to carry and sell materials which are often unsuitable in our environment. With so little empirical data to go on, rhododendron culture in the Atlanta area, even for the more knowledgeable, is largely trial and error, and with a large percentage of error.

In making my survey of suitable hybrids and species, I limited myself to interviewing members of the Azalea Chapter who have greater than average experience in rhododendron culture thereby reducing the impact of failures in that statistics due mainly to ignorance and poor horticultural methods.

Where undisturbed the top soil in the Atlanta area contains considerable humus, but the ubiquitous red Georgia clay underlying North Georgia is a source of much frustration. Generally the people who were interviewed use similar horticultural methods. They use elevated beds and slopes and good amounts of organic materials in the soil to improve drainage. Usually they plant under the high dappled shade of pines and oaks, fertilize in March or April, water when dry, mulch adequately, and worry a great deal.

It is hoped that this initial rating will provide our membership and the nursery trade with useful information on hybrids and species which seem suitable in this area, given good care and the best environmental conditions locally available. It is not intended to discourage experimentation with new hybrids or other species, but merely to provide a basis upon which our membership and the nursery trade can proceed with greater assurances of success.

S-satisfactory plant and flower

P-satisfactory plant, no flowers as yet

U-unsatisfactory, little adaptability or capacity to survive