Azaleas and Rhododendrons: What is the Difference?

Producing a blaze of color from early spring through the summer and even into the fall, Azaleas and Rhododendrons are popular ornamental shrubs for gardens of all sizes. But what is the difference between Azaleas and Rhododendrons?

Once classified in separate plant groups, Azaleas, and Rhododendrons are now placed together in the genus Rhododendron because of their many common characteristics. Gardeners and nurseries continue, however, to make the distinction, referring to each by their common name.

The classification can be complex due to the large number of species and hybrid varieties, often leading to confusion between the two. However, they do have key differences that can help distinguish them.

• Leaves: Rhododendrons generally have larger, thicker, and leathery leaves. Some species have a coating of scales or a ‘felt-like’ covering underneath. Azaleas, on the other hand, have smaller, thinner leaves, and the undersides are typically smooth and lack any noticeable texture.
• Flowers: The flower structure is a key difference. Azalea flowers usually have five stamens (the male part of the flower), while rhododendron flowers have ten or more. Azalea flowers often appear funnel-shaped, with petals fused along the sides, while rhododendrons display larger, bell-shaped flowers.
• Blooms: Azaleas are known for their vibrant displays, with entire shrubs often covered in blooms. They bloom in various colors, including pink, purple, red, orange, and white. Rhododendron blooms tend to be larger and denser, and the color range includes white, pink, red, and purple, and some species offer yellow and nearly blue flowers.
• Growth Habit: Generally, most azaleas are deciduous, shedding their leaves in the fall, while most rhododendrons are evergreen, keeping their leaves throughout the year. However, there are exceptions, with some azalea species being evergreen, particularly in warmer regions.
• Size: Rhododendrons tend to be larger shrubs, some growing into small trees, while azaleas remain smaller, bushier plants.

Azalea

• May be deciduous or evergreen
• Leaves tend to be thin and soft, often hairy
• Leaves never have scales
• Flowers typically have 5 or 6 stamens
• Evergreen Azaleas generally have 1 to 3 flowers at the end of each stem
• Many small stems