Beautiful Blooming Rhododendrons
Driving around Ocean Shores, one will see numerous rhododendrons of assorted sizes and colors. Some seem healthy and strong with vibrant blooms, while others may look lanky and pale. Rhododendrons can be magnificent colorful garden companions in coastal areas like ours where the climate and conditions are favorable…and the deer stay away from them for the most part. However, to ensure they thrive in our unique environment, specific care practices are essential.
Before diving into care techniques, it is important to choose rhododendron varieties well-suited to the coastal climate. If you are considering adding a rhododendron to your landscape, opt for varieties that are hardy and resistant to common pests and diseases in the region. Some recommended varieties include ‘Cunningham’s White’, ‘Nova Zembla’, and our native Pacific Rhododendron. These are ones that will enjoy our cooler temperatures, but they will likely need some protection from the winter winds. Early autumn or spring are great times to plant rhododendrons.
Rhododendrons, often lovingly called “rhodies”, prefer partial shade, which of course is abundant along the Washington coast due to frequent cloud cover. Morning sun with afternoon shade is ideal.
These plants thrive in well-draining, acidic soil. Our coastal soil is often sandy, so amending it with organic matter such as peat moss, compost, and/or leaf mold can help retain moisture and provide them with the nutrients they need.
Consistent moisture is crucial for rhododendrons, especially for younger plants. Even established rhodies will benefit from extra watering during dry summer periods. Water deeply and regularly, ensuring the soil remains moist but not waterlogged. Applying a 2-3” layer of mulch around the base of the plants will help retain moisture, regulate soil temperature, and suppress weeds.
The time to fertilize is in early spring before new growth starts and, if necessary, again after flowering. Use fertilizer specially formulated for acid-loving plants like azaleas, rhododendrons, and camellias.
Maintaining the soil pH between 5.0 and 6.0 is important for rhodies. Regularly test the soil and amend it with sulfur if the pH levels rise too high (i.e. becomes too alkaline).
Rhododendrons will benefit from some light pruning right after they finish flowering. This ensures you do not accidentally remove the buds for next year’s blooms. Remove dead or diseased branches and spent flowers. Lightly shape the plant to maintain a desirable form but avoid heavy pruning as rhododendrons can be slow to recover.
Healthy plants generally avoid many of the common rhododendron pests found on the Washington coast which include lace bugs, spider mites, and thrips. It is always a good idea to monitor your plants regularly and treat infestations with insecticidal soap or horticultural oil as needed. And good air circulation is key to preventing fungal diseases. Avoid overhead watering to reduce the risk of fungal diseases such as leaf spot and powdery mildew. If necessary, treat with appropriate fungicides.
Rhododendrons can be a stunning addition to any garden along the Washington coast, providing vibrant color and lush greenery. By selecting the right varieties and following common care guidelines, you can ensure your rhododendrons thrive in our unique coastal environment. Regular watering, proper soil management, and timely pruning will keep your plants healthy and beautifully blooming year after year.
If you would like more information about this article, or how to get involved at Garden by the Sea, please contact us at info@gardenbytheseaoceanshores.org
