The Stunning Beauty of Fully Grown Evergreen Azalea Stewartstonian

The Stewartstonian azalea (Rhododendron ‘Stewartstonian’) is a gorgeous broadleaf evergreen shrub that delivers an incredible display of color in spring gardens. When allowed to reach its mature size over 3-5 years, this plant truly comes into its own, blanketing itself in masses of bright reddish-orange blooms. If you have the patience to nurture a young Stewartstonian azalea to full maturity, it will reward you with unrivaled springtime beauty year after year.

Overview of Stewartstonian Azalea

Stewartstonian azalea is a member of the Gable hybrid group originally bred by Joseph Gable of Stewartson, Pennsylvania. This medium-sized shrub grows to around 4-5 feet tall and wide at maturity. It has deep green, glossy foliage that takes on chocolate-red hues in fall and winter.

The real showstopper is the profusion of large, trumpet-shaped orangey-red blooms that cover the plant in spring. Flowering lasts 2-3 weeks and is highly fragrant. This azalea does best in zones 5-8. It prefers rich, acidic, moist soil and afternoon shade, especially in hot climates.

The Benefits of a Fully Mature Shrub

One of the Stewartstonian azalea’s virtues is its slow growth rate. It can take up to 5 years to fully establish and display its mature form. But once it reaches its full size, this plant really struts its stuff. Here are some key advantages of a full grown specimen

• Abundant spring bloom – A mature plant can produce hundreds of flowers, delivering a saturation of color. Few other shrubs flower as prolifically.

• Maximum impact: The bright orange-red flowers make a strong statement and look great against the green leaves.

• Increased flowering – Older plants produce more flowers each year as they continue growing. Proper pruning encourages vigorous growth and more blooms

• Good leaf coverage—Once the plant has grown its leaves, the glossy green ones do a great job of hiding it. Reddish fall color is a bonus.

• Better resistance to drought—plants that have been around for a while are better able to handle short-term droughts. Their extensive root systems can better access soil moisture.

• Less maintenance – Growth rate slows down dramatically once mature. Pruning, watering, and fertilizing requirements are lessened.

Growing Strong Stewartstonian Azaleas

Here are some tips to help your Stewartstonian azalea thrive:

• Site in part sun or light afternoon shade, especially in hot climates. Dappled sunlight is ideal.

• Plant in rich, acidic, moisture-retentive soil amended with compost or pine needles.

• Water 1 inch per week until established (2+ years). Mature plants only need watering during drought.

• Apply acidic fertilizer annually and mulch well with pine needles or bark chips.

• Prune selectively immediately after blooming to shape the plant. Never shear into tight globes.

• Monitor for pests like lace bugs and caterpillars. Use organic treatments first before chemical controls.

Where to Use Fully Grown Stewartsonian Azaleas

The striking floral display of a mature Stewartstonian azalea lends itself to many uses:

• Plant as a focal point or specimen shrub. Give it room to reach its full size.

• Group together for a high impact color display in spring. Space plants 3-4 feet apart.

• Use as an anchor in borders or foundation plantings combined with lower-growing plants.

• Flank walkways, entryways or patios to showcase the beautiful blooms.

• Include in woodland gardens with ferns, hostas and other shade lovers.

• Plant in rock gardens, raised beds or large containers. The shallow roots adapt well.

Caring for a Mature Shrub

Proper care is key to keep a full grown azalea looking its best:

• Water deeply once a week in droughts. Mature plants are quite drought-hardy otherwise.

• Fertilize in early spring and after flowering with an acidic fertilizer formulated for azaleas.

• Prune after blooming to shape the plant. Never shear or prune heavily.

• Mulch annually with 2-3 inches of pine bark to maintain soil moisture and acidity.

• Monitor for common pests like lace bugs and spider mites. Treat only if infestations occur.

• Deadhead spent blooms to prolong flowering.

• Avoid disturbing the roots once established. Stewartsonian azaleas dislike transplanting.

With the proper long-term care, a mature Stewartstonian azalea will thrive for many years. The wait for it to reach full size is well worth it to enjoy the full flowering potential of this spectacular plant. Just be sure to provide the growing conditions it needs. The beauty of a fully grown azalea Stewartstonian is truly breathtaking to behold in the spring landscape.