This hybrid evergreen, dense-growing rhododendron thrives in semi-shade in cooler regions as a foundation or accent shrub.
Be mindful that all parts of the plant are toxic if ingested by humansand pets.
Learn how to grow and care for this spectacular plant.
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Rhododendron English Roseum Care
Here are the main care requirements for growing Rhododendron English Roseum.
Light
This is a woodland shrub that will not thrive in full, harsh sun.
Plant in an area withdappled sun or partial shade.
Soil
The soil should be loose and organically rich with good drainage.
Water
Rhododendrons like moist soil but can tolerate slightly dry times.
Mulch around the plant to help retain moisture but do not overwater.
Temperature and Humidity
Rhododendron English Roseum prefers a cooler climate with lower humidity.
It is best suited for USDA Hardiness Zones 4a-7b.
Fertilizer
Fertilize yearly in the spring after the blooming period.
The fertilizer should be acid-based.
Working compost into the soil will provide the pH needed.
If pruning the shrub, fertilization should be done about one month before pruning.
The best time to prune is right after they have finished blooming and new growth begins.
Pruning is particularly important for young plants to increase branching and flower production.
When new growth begins on young plants, snip out any single shoots so that multiple branches will grow.
This will cause the plant to produce new shoots along the main stems adding foliage where it is needed.
Propagating Rhododendron English Roseum
This rhododendron can be propagated using cuttings or by layering.
Layering is the easiest method and can be done in the spring or early summer.
Softer wood roots more readily than harder wood.
Cuttings should be taken in the morning when they are full of moisture.
Start the seed indoors in late January or February.
If those conditions are predicted,wrap the shrubin burlap.
Don’t forget to remove the burlap once the weather warms.
Common Pests and Plant Diseases
Several insects can cause damage to Rhododendron.
There are many commonfungal leaf spotpathogens ofRhododendronspp.
but most do not cause serious harm and are cosmetic.
Do not overfertilize mature plants, as you’ll get more leaves than blooms.
Avoid pruning in late winter or early spring, or you risk removing the buds that will become flowers.
Deadhead the spent blooms to encourage new bud production.
Protect the shrubs during bitterly cold weather and heavy snows or ice storms.
How long does Rhododendron English Roseum bloom?
The shrub can bloom for two to five weeks depending on weather conditions.
What do Rhododendron English Roseum flowers look and smell like?
The flower heads are held in dome-shaped trusses of 8-10 flowers.
The rosy, lilac pink blooms are funnel- or bell-shaped with 10 stamens.
While some rhododendrons are fragrant, the English Roseum hybrid is not highly perfumed.
Common Problems with Rhododendron English Roseum
Even with proper care, there are a few common problems.
Leaves Turning Yellow
Soil that is too alkaline can cause leaves to turn yellow.
Rhododendrons need acidic soil.
To help correct the problem,amend alkaline soilwith compost or acid-based fertilizers.
Wilting Leaves
Overwatering or drought can cause wilting or drooping leaves.
Keep the soil moist and be sure to mulch plants well.
Rhododendrons that are well-tended can live for decades.
English Roseum was introduced in the 1950 and many original specimens are still thriving.
Choose a spot that is not located in full sun; the shrub thrives in dappled or partial shade.
The location should have good drainage and avoid low-lying areas.
The shrub works well as a specimen plant in the garden or a foundation plant.
Choose a dwarf variety such as Rhododendron x ‘Cunningham’s White’ or Rhododendron x ‘Landmark’ instead.
Rhododendron catawbinese.North Carolina Extension Plant Toolbox.
