Rhododendrons and Azaleas, what is the difference anyway?
All Rhododendrons are evergreen which means that they will hold leaves all winter long. Most Azaleas on the other hand (under the same Genus of Rhododendron) will lose their leaves at the end of the season. The other difference is that true Rhododendrons have ten or more stamens, 2 per lobe and Azaleas have only five stamens – one per lobe and 5 lobes in a flower.
The above picture of a Rhododendron showing its nice red-purple fall color. Notice the older leaves will color and drop even though it is an evergreen. The newer leaves are at the tips of the branches and will be retained all winter long.
Azaleas typically have nice fall as well and many will lose their leaves later in the season. Sometimes Azaleas in warmer climates hold their leaves.
Rhododendrons appreciate good fall moisture and love to have a nice 3” layer of mulch over their roots. The older, more interior red-purple leaves will drop from the plant and it is a very normal occurrence.
In colder climates and where your plants are exposed to winter winds you may want to consider some wind protection or maybe a spray on anti-transpirant later in the season to prevent the leaves from drying out.
Both Rhododendrons and Azaleas are best pruned right after they bloom in spring only so hold off pruning this fall.