What: Rhododendron “Blue Danube” is a selection of evergreen azalea that becomes covered with flowers in late April to early May. The large, hot magenta flowers glow with a deeper purple red throat, adding a sense of depth to the bloom. This old Belgium cultivar has a vigorous growth habit, becoming an attractively tiered shrub as it matures.
Where: Plant it in rich well-drained or sandy soil in a location with full sun to light or open shade.
Size: The evergreen shrub grows to be 4 feet tall and 5 feet wide when mature.
Care: This azalea is easy to grow in the Pacific Northwest. Azaleas are shallow-rooted plants, requiring regular watering during dry weather. Faded flowers often drop off or are quickly covered by new growth. Almost no pruning is needed to keep azaleas looking good. Adult root weevils can chew on their leaves, but this is less of a problem on plants that receive more light and regular watering.
— Richie Steffen, Great Plant Picks