Azaleas are flowering shrubs in the genus Rhododendron, particularly the former sections Tsutsuji (evergreen) and Pentanthera (deciduous). Azaleas bloom in the spring, their flowers often lasting several weeks.
The Ericaceae are a family of flowering plants, commonly known as the heath or heather family, found most commonly in acid and infertile growing conditions. The family is large, with c. 4250 known species spread across 124 genera, making it the 14th most species-rich family of flowering plants. The many well-known and economically important members of the Ericaceae include the cranberry, blueberry, huckleberry, rhododendron (including azaleas), and various common heaths and heathers (Erica, Cassiope, Daboecia, and Calluna for example).