This species of Rhododendron is native to the Appalachian Mountains in the eastern United States, ranging from southern Pennsylvania and Ohio to northern Georgia.

[6] The inflorescences of Rhododendron calendulaceum are visited by many animals such as bees, butterflies, hummingbirds and small mammals.

The flowers of Rhododendron calendulaceum can range from light yellow to orange and rarely, a scarlet red.

[8] The inflorescences of Rhododendron calendulaceum are visited by a diverse group of animals such as bees, butterflies, hummingbirds and small mammals.

E. vaccinii negatively affects the reproduction and health of the flowers and branches of Rhododendron calendulaceum.

[12] This species of Rhododendron is native to the Appalachian Mountains in the eastern United States, ranging from southern Pennsylvania and Ohio to northern Georgia.

[13] It has been reported historically in New York and Maryland, however, its current native status in these states is undetermined.

It is found in the well-developed shrub layer of oaks with southern and western sun exposure.

Rhododendron calendulaceum is an important understory shrub in forests that were formerly co-dominated by the American chestnut.

[15] Rhododendron calendulaceum grows in well-drained, mesic to moist, medium to fine textured soils in part shade.

[7] It is also an important parent species in hybrid Azaleas, such as Ghent, Knap Hill, Maid in the Shade, Mollis and Northern Lights.