Stewartstonian Azalea Plant Profile

All the Red You Could Want From One Plant

Stewartstonian azalea with its red flowers
David Beaulieu

Not all azaleas are created equal. Stewartstonian azaleas have more to offer than most. Their red flowers in spring are real show-stoppers and also draw butterflies to your yard. In fall, their leaves turn red.

Some azaleas are bare in winter, but not Stewartstonian azaleas. For example, plants in the Exbury group, which includes such standouts as Golden Oriole azalea (Rhododendron Golden Oriole) and Gibraltar azalea (Rhododendron x Gibraltar), drop their leaves in winter. But Stewartstonian azaleas retain their leaves, which assume a mahogany color in December and lend winter interest to your landscape.

How to Grow Stewartstonian Azalea

Stewartstonian azalea requires a moderate amount of maintenance. Locating it at planting time in partial shade and in a soil that drains properly is a good start. But you also have to keep it irrigated, fertilized, and pruned.

Prune Stewartstonian azalea after it is done flowering to shape the bush, as needed. These are shrubs that flower on old wood.


Along with mulching, giving the shrub sufficient shade will help it stay hydrated.


Enrich the ground (and improve its drainage at the same time) by mixing in generous amounts of decomposed organic matter.


You must keep the soil moist for this plant throughout the growing season, and applying mulch will help the soil retain the moisture it needs.


Fertilize annually with compost.

Best Features of Stewartstonian Azaleas

Flowers are wonderful, but, the longer you garden and the more you pay attention to the changes in your plants as the four seasons unfold, the greater will grow your appreciation for attractive foliage. So let's take a look at the evolution of Stewartstonian azalea's leaves during the course of a year (using a bush located in zone 5 as an example):

By the time the new year rolls around, the shrub will have mahogany-colored leaves; the color is very dark. By March, red starts to work its way into the color mix, although the hues are still quite dark. In late June, there is another color transformation: The summer sun puts the darkness to rout, and the leaves become medium-green.

Early August witnesses the first hints of the fall color to come, as a few leaves turn red. But we must categorize this shrub as a plant for late fall foliage: It is not until early November that red gains the upper hand. By late November the bush is totally red, except for the newest leaves, which are mahogany.

In December, the older, red leaves drop off, leaving the newer, mahogany ones in control. This final change brings us full circle, as those newer leaves will stay on through the winter and be the foliage that your Stewartstonian azalea starts out with next spring.

Origin of the Name

The "x" in the botanical name indicates that this is a hybrid plant, while the succeeding names are references to its developer (Joseph Gable) and where he lived (Stewartstown, PA, U.S.), respectively.

Landscaping Uses

Azaleas are among the most popular spring flowers in North American landscaping and should be given a location where you can easily take in their beauty as you go about your daily chores in spring. Nor do you have to worry, with Stewartstonian, that, after blooming is finished, the bush will just be "taking up space." Its attractive foliage warrants labeling Stewartstonian azalea a four-season landscaping plant.

Some specific landscaping uses for these bushes include:

Moreover, their shallow root systems make azaleas relatively safe plants for septic tank drain fields.

Plant Relatives

Azaleas are in the heath family. This means that they are related to, for example: