Rhododendron viscosum, the swamp azalea, clammy azalea or swamp honeysuckle, is a species of flowering plant in the heath family Ericaceae. This deciduous shrub, growing to 2.5 m (8.2 ft) tall and broad, is native to the eastern United States. It has rounded matt green leaves.

Rhododendron viscosum, commonly known as swamp azalea, is a loose, upright-spreading, deciduous woody shrub that typically grows to 3-5' (less frequently to 8') tall. Branching opens up with age. It is one of 17 species of azalea which are native to the U.S.