A deciduous, stoloniferous shrub up to 3 ft high; young shoots glabrous apart from scattered appressed hairs and occasional glandular hairs. Leaves obovate to oblong-obovate, rounded to subacute at the apex, cuneate at the base, light green or bluish green above, green or slightly glaucous beneath, usually glabrous on both surfaces apart from the slightly hairy midrib. Flowers fragrant, borne in May with or slightly before the leaves in clusters of four to ten, very fragrant, on hairy pedicels up to 1⁄2 in. long. Calyx up to 1⁄/6 in. long, glandular-ciliate. Corolla white, flushed with pink outside, tubular-funnel-shaped, the tube glandular, 1 to 11⁄2 in. long, rather gradually widening to the limb, which is 11⁄4 to 11⁄2 in. across; lobes acute, each with a line of stalked glands along the midrib outside. Stamens about twice as long as the tube. Ovary clad with bristly, sometimes gland-tipped, hairs; style longer than the stamens. (s. Azalea ss. Luteum)
Native of the eastern USA in the coastal plain from Delaware to South Carolina; introduced to Britain in 1922. 'In late April and early May the Coast azalea makes a truly splendid sight as a multi-hued understory to the open pine woods of the coastal Carolinas. Since it is highly stoloniferous it recovers promptly in the wake of a brush fire or roadside trimming or grazing, so that the year following will again see hundreds of upright flower clusters on wiry, knee-high stems borne by one plant an acre or more in extent' (H. T. Skinner, R.C.Y.B. 1957, p. 13). In this article, Dr Skinner suggests that typical R. atlanticum, described mainly from plants growing in Virginia and the Carolinas, may be the result of introgression of genes from R. canescens and R. nudiflorum, and that the original form of the species, uncontaminated by hybridisation, is represented by plants found in Delaware, which are white-flowered and far more glandular than typical R. atlanticum.
R. atlanticum is an azalea of great charm, very hardy and growing vigorously in moist soil. But flowering as it does at the peak of the rhododendron season it will go unnoticed unless planted well away from its more flamboyant rivals. It associates well with low-growing herbaceous plants.
The Award of Merit was given on May 25, 1964 to the clone 'Seaboard', exhibited by the Crown Estate Commissioners, Windsor Great Park.