Rhododendron, sometimes referred to as Azalea, is a genus of 1024 species of woody plants in the heath family, Ericaceae, either evergreen or deciduous, and found mainly in Asia with a few species found in other parts of the northern hemisphere. Most species have showy flowers for which they are prized and widely cultivated. The genus name is derived from the Ancient Greek words rhódon meaning rose and déndron meaning tree. Both species and hybrid rhododendrons including azaleas are used extensively as ornamental plants in landscaping in many parts of the world, including both temperate and subtemperate regions, while many species and cultivars are grown commercially for the nursery trade. Rhododendrons are often valued in landscaping for their structure, size, flowers, and the fact that many of them are evergreen. Azaleas are frequently used around foundations and occasionally as hedges, and many larger-leafed rhododendrons lend themselves well to more informal plantings and woodland gardens, or as specimen plants. In some areas, larger rhododendrons can be pruned to encourage more tree-like forms.

Rhododendron maximum, commonly known as Great Laurel, Great Rhododendron, Rosebay Rhododendron, American Rhododendron and Big Rhododendron, is an evergreen shrub usually growing to 4 m in height, but rarely reaching up to 10 m. It is native North America from Ontario and Nova Scotia south to Ohio, Alabama, and Georgia in the Southeastern United States where is can be found growing in the southern Appalachian region. During summer it produces large, showy, white to pink to purple flowers. Rosebay rhododendron is mainly cultivated for use as a striking and aesthetically pleasing feature plant in gardens and parks. The wood is very hard and is occasionally used for specialty wood products.