Rhododendron viscosum var. serrulatum, commonly known as the hammocksweet azalea, toothed azalea, or swamp azalea, is a deciduous, highly fragrant native shrub belonging to the Ericaceae family.

While some botanical authorities treat it as a distinct species (Rhododendron serrulatum), others classify it as a southern variety of the classic swamp azalea (Rhododendron viscosum).

Unlike most native azaleas, this species pushes its blooms exceptionally late into mid-to-late summer, often flowering from July through September.

This species does well in partial shade to full filtered shade and will require deep, acidic, consistently moist to wet soil.  Because of these high moisture needs, it will do well for rain gardens.

Host plant for the Azalea Sphinx and the Rhododendron Borer Moth, as well as the Brown Elfin Butterfly.