If you have often heard rhododendron vs azalea being compared to one another, you may want to know the reason why. Growing as large shrubs and plants in a variety of locations around the world, rhododendrons and azaleas are directly related to each other. But in what way are they related, and how can you learn how to tell these two plants apart?
In this article, we will compare and contrast rhododendrons and azaleas so that you can fully understand the similarities and differences between these two plant species. Besides addressing how they are related to one another, we will go over what they look like and what these flowers are typically used for. Finally, we will give you the growing preferences of both rhododendrons and azaleas so that you can plant some in your own backyard. Let’s get started!
Comparing Rhododendron vs Azalea
|Rhododendron plant family
|Rhododendron Azaleastrum subgenus
|Large and smooth leaves cover these large shrubs, with clustered flowers in a variety of colors. These flowers grow in bunches and are bell-shaped, with more than 5 stamens present. Flowers and leaves are much larger than azalea varieties
|Pointed and small leaves make up this variety of shrub, with beautiful blooms found in a variety of colors. Flowers are funnel-shaped and grow closely together, but not always in clusters. Only 5 stamens are present, and the leaves and flowers are much more narrow compared to rhododendron varieties
|An extremely popular plant family for shrubs and privacy plants; having leaves year-round keeps the garden looking full and alive. May also have some health benefits
|Popular shrub for its ornamental blooms and leaves; deciduous varieties make gardens change with the seasons and its overall hardiness makes it a great plant for beginners
|Origin and Growing Preferences
|Native to the Himalayas and Asia; prefers dappled sunlight and nutritious soil, but make sure to avoid cold or drafty locations
|Native to Japan and China; prefers a variety of growing conditions, more hardy compared to rhododendron overall. Consistently moist soil works best
|Leaf Qualities and Shrub Size
|Evergreen leaves; ranges in height from 3-20 feet, depending on variety
|Deciduous leaves; ranges in height from 1-15 feet, depending on variety
Key Differences Between Rhododendron vs Azalea
There are a number of key differences between rhododendrons and azaleas. While all azaleas are technically rhododendrons, not all rhododendrons are azaleas. In addition, most rhododendron varieties are larger in height, leaf size, and flower size compared to the more petite azalea. Finally, most azalea varieties are deciduous, While most rhododendron varieties are evergreen.
Let’s go over all of these differences in more detail.
Rhododendron vs Azalea: Classification
The reason that rhododendrons and azaleas are commonly compared with one another is because they are directly related. In fact, rhododendron refers to the entire plant family that azaleas belong to, as azaleas are a very specific subgenus of rhododendron. This essentially means that all azaleas are technically rhododendrons, but not all rhododendrons are azaleas, giving them some subtle but significant differences in appearance.
Rhododendron vs Azalea: Description
Speaking of subtle differences in appearance, you may not be able to tell a rhododendron shrub apart from an azalea shrub right away. However, there are some things to keep an eye out for as you learn about these two plants. For example, rhododendrons tend to be larger than azaleas in just about every way, including height, leaf size, and flower size. For the most part, rhododendron plants are flashier and showier compared to azalea plants.
This isn’t to say that azalea plants don’t provide their own beautiful blooms, as both rhododendrons and azaleas come in countless colors and flower shapes. However, rhododendron flowers are typically clustered together and have more of a bell shape compared to the trumpet shaped azalea flowers. In addition, the leaves of the azalea shrub are typically more narrow compared to the wide and leathery leaves found on most rhododendron shrubs.
Rhododendron vs Azalea: Uses
Rhododendrons and azaleas are extremely popular around the world, given their fantastic growing abilities and attractive appearance. Both of these shrubs are commonly used as privacy or as ornamental shrubs in backyard gardens, though the rhododendron is often utilized for gardens that need more height compared to the more petite azalea plants. In addition to this, rhododendron plants are being studied for their medicinal uses, though there is much more research that needs to be done.
Rhododendron vs Azalea: Origin and How to Grow
Given that they are directly related to one another, rhododendrons and azaleas have similar origins and preferences for how they grow. However, there are some differences between them in this respect as well. For example, rhododendrons are native to the Himalayas and parts of Asia, while azalea plants are native to Japan and China primarily.
In addition to their origins, rhododendrons and azaleas have slightly different growing preferences, depending on the variety. For example, most rhododendron bushes are fussier than azalea shrubs, especially when it comes to cold weather. Both of these plants enjoy partial shade and nutritious soil, but rhododendron plants prefer to grow away from any cold drafts or high winds, while the azalea plant is more hardy overall.
Rhododendron vs Azalea: Leaf Qualities and Shrub Size
The final difference between rhododendrons and azaleas has to do with their leaves and evergreen qualities, as well as how tall they get on average. For example, most rhododendron plants are evergreen, While most azalea plants are deciduous. This means that the azalea plants will change with the seasons and earn reddish-brown leaves in the fall, while rhododendron plants stay green year-round. In addition to this, many rhododendron varieties grow larger than azalea plants, but it depends on the specific varieties you are comparing with one another!
- Gardenia vs Camellia: Key Differences
- Fiddle Leaf Fig vs Bambino: Is There a Difference?
- Gooseberry vs Currant: What is the Difference?
The photo featured at the top of this post is © iStock.com/dndavis
Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.
- Bioactive compounds, health benefits and utilization of Rhododendron: a comprehensive review, Available here: https://agricultureandfoodsecurity.biomedcentral.com/articles/10.1186/s40066-019-0251-3