Last week I bought 3 Azalea vaseyi. How big will they grow? Can they be pruned for a poolside garden? Are they slow growers? Do they like acid fertilizer like Rhodos?
Azalea vaseyi (Rhododendron vaseyi) is a native plant to North America found in the mountainous area of North Carolina. Due to its native habitat, it can withstand low temperatures in northern areas. Just like other Rhododendrons, it grows in moist, fertile, humus-rich acidic soil (pH 4.5 to 5.5) in part to full sun. Plant shallow as plants are surface rooted and like a mulch covering, ensure good drainage.
In terms of growth habit, just like any Rhododendron, it will grow according to its conditions. It is considered a small shrub even though in the wild, it can grow up to 12’. In an urban garden it will grow approximately to a height of 5’ (150cm) after 10 years, and with the right conditions, it will grow to its expected size eventually. The plant’s form and size can be controlled by pinching out the soft, new shoots of vigorous growing plants. Hold the stem with one hand, and pinch the new growth between your fingers right at the bud. Do this as you see the new growth developing.
Discontinue pinching the new growth after July. However, only do it when necessary and not often as it will drain the energy from the shrub. Enjoy these beautiful specimens next fall (good foliage colour) and early spring (gorgeous flowers)!