Growing rhododendrons and azaleas helps to define the landscape style of the Pacific Northwest. Varied and vivid flower colors brighten shady sites through the spring months, and bold evergreen foliage gives a lush appearance all year long.
Though some varieties have reasonable sun tolerance, all are easier to establish and maintain where protected from the hottest exposures. Plant azaleas and rhododendrons in a location where they’ll have protection from wind and direct afternoon sun. Generally, choosing an east or north facing location works well.
Both plants require well-draining soil that is high in organic matter. Add plenty of acid plant planting mix, like G&B Organics Acid Planting Mix, to loosen up clay soils. If your soil has too high of pH (alkaline conditions) then your plants may eventually become discolored, and potentially die.
When planting, dig a hole twice the width of the root ball and to the same depth the plant is sitting in its pot; when placed in the hole the top of the root ball should slightly above the surrounding soil line. Keep rhododendrons and azaleas and their shallow root systems well watered in the dry summer months, though be mindful not to over water as they do not thrive in wet soils.
Fertilize at planting, or soon after flowering, to maximize next year’s blooms. Choose an acid plant fertilizer such as G&B Organics Rhododendron, Azalea, Camellia Fertilizer. If pruning is necessary, prune soon after flowering in spring as bud formation occurs quickly after bloom for the following year.
While rhododendrons and azaleas can be planted year round in western Oregon, shopping in spring gives you an opportunity to see different varieties in flower before choosing one to take home. Planting in early spring when soil moisture is high and air temperatures are cool can be less shocking for a new planting. Use mulches to control weeds, retain moisture and maintain consistent soil temperatures through the year.
– Darren Morgan & Rachel Barnhart