Rhododendron macrophyllum, commonly known as the Pacific Rhododendron or California Rosebay, is a species of rhododendron native to the Pacific Northwest region of North America, particularly in coastal areas from British Columbia to northern California.
This stunning broadleaf evergreen shrub typically grows to heights of 5 to 15 feet (1.5 to 4.5 meters) but can occasionally reach up to 30 feet (9 meters) in optimal conditions. It features large, leathery leaves that are elliptical to oblong in shape, measuring 4 to 10 inches (10 to 25 centimeters) in length. The leaves are dark green and glossy on the upper surface, with a lighter green underside.
In late spring to early summer, Rhododendron macrophyllum produces showy clusters of bell-shaped flowers at the ends of its branches. The flowers vary in color from pale pink to deep rose and are marked with darker spots or blotches. Each cluster can contain numerous individual blossoms, adding a splash of color to the woodland understory.
Pacific Rhododendron is typically found in moist, acidic soils in shaded to partially shaded locations, such as coniferous forests, coastal scrublands, and along stream banks. It thrives in mild coastal climates but can also tolerate colder inland regions with protection from harsh winds and extreme temperatures.

Growing Instructions for the Rosebay Rhododendron

The seeds like moist, well-drained soil. 1. Fill a container with sterile soil or a sterile seed starter mix. 2.  Sow the seeds on the surface of the soil. The seeds need light to germinate. 3. Water the soil so that it is moist but not wet. The seeds take 10 to 20 days to germinate. 4. When the seedlings are a few inches tall, they can be transplanted.