Evening Glow Rhododendron

For most people, say the word ‘rhododendron’ and they will tell you a pink or red shrub that flowers in early spring. But the world of rhododendrons is a large one, and if you can imagine a color, there will be a variety in that color. Let’s imagine yellow. Well, there is the Evening Glow Rhododendron, a beautiful and very special variety with large, bright yellow flowers, like evening suns, which come right at the very end of the season, after all the pinks, whites, reds and purples. It makes the perfect transition from those typical colors of spring into the summer palette of – yes, you guessed it – yellows, oranges and burnt pinks, like black-eyed Susan, cone-flowers, daylilies and other symbols of the summer garden.
This beautiful, unique variety forms a large, upright evergreen bush. Certainly it will be 5 feet tall and wide within a short 10 years, and one day double that, or even more. So allow plenty of room for its future growth, or its beauty will be crushed and buried, never to have the freedom to show you just what it can do. Use it as a background to smaller acid-loving shrubs, knowing that they will have stopped flowering before the Evening Glow Rhododendron begins. So no risk of color clashes spoiling your spring display – no, just a delicious transition into summer from a truly beautiful and unique rhododendron.

Growing the Evening Glow Rhododendron

Size and Appearance

The Evening Glow Rhododendron is a medium-sized evergreen shrub, with an upright habit, making a dense, rounded plant. It grows about 6 inches a year, and within 10 years it will be 5 feet tall and wide. Of course it won’t magically stop growing, and it will continue to add those 6 inches each year. One day not so far away it will be 10 feet by 10 feet, a magnificent addition to your garden beds. So when planting, make sure you leave enough room for its future growth (use perennials or something shorter-lived to fill the spaces around it while it develops).
The leaves are 6 to 7 inches long, with a non-glossy (matte) surface of mid-green, quite different from many other varieties, with their deep-green, glossy leaves. Otherwise they are similar, with a smooth surface and edges, and a slender oval form. Leaves stay for two years, before dropping in the early summer, after new shoots have formed. This extra year means an exceptionally dense and bushy plant.

It blooms late in the season, among the very last varieties of rhododendron to flower, which means late June in most areas. It’s a fabulous way to extend the rhododendron season. The flowers are large, 3½ inches across, orange-yellow in bud, opening to be light yellow on the outside, with a deeper yellow interior, deepening even more into the throat. Unusually, even the special leaves that protect the bud (called sepals and forming the calyx) are yellow and noticeable, rather than the much more usual bland green. Prominent stamens thrust from the flower, completing the picture of beauty. The flowers are gathered together in heads (called trusses) at the end of each bud, with between 7 and 11 flowers in each truss, arranged in an open display, not the dense heads seen in many other varieties of rhododendron.

Using the Evening Glow Rhododendron in Your Garden

Why let the rhododendron season end abruptly? By growing late-blooming varieties like the Evening Glow Rhododendron you can extend the season by several weeks, and enjoy these lovely evergreen shrubs for even longer. Grow this upright, dense shrub behind smaller rhododendrons, to appear after those are over, or with later blooming shrubs, like hydrangea, to be the heralds of the summer to come. Allow room for final sizes, and bring bulk and structure to your garden.

Hardiness

The Evening Glow Rhododendron will grow best in zones 6, 7 and 8, in areas where the summers have some rain and are not extremely hot and dry. This is not a drought tolerant plant

Sun Exposure and Soil Conditions

Some morning sun will keep your Evening Glow Rhododendron healthy and vigorous, producing lots of blooms. More shelter in the afternoons, with some shade, is idea. The soil needs to be acidic, with a pH value of no more than 6.5, and preferably closer to 5.5 or even 5.0. The earth should be well-drained – not wet and boggy, but at the same time it is best to be regularly moist. That can be helped a lot by adding plenty of organic materials, like rotted leaves, pine needles and peat moss when digging the planting area. Make sure the materials you use are free of lime. Use similar materials as mulch in spring over the root zone of your plants.

Maintenance and Pruning

Get the soil, moisture and light correct, and the Evening Glow Rhododendron becomes a very easy shrub to grow. You won’t find deer grazing it, or rabbits (the leaves are toxic, but rarely eaten by pets). Pests or diseases are rare, and you can trace any problems to soil conditions, rather than diseases. No pruning is required and we strongly recommend you don’t attempt to prune. Simply snap out the dead flower trusses once all the petals have fallen, being sure not to remove any leaves, and keep the new shoots growing from the base of the old flower stem safe and undamaged. At first this deadheading can seem challenging, but with a little practice is it s breeze. By doing this you encourage more flowers for the following season.

History and Origin of the Evening Glow Rhododendron

Rhododendron dichroanthum is another one of the incredible species found in Yunnan, and introduced by George Forrest to England in 1906. It has beautiful bell-shaped orange-red flowers. Rhododendron griersonianum also comes from Yunnan, and has brilliant red/orange blooms. It was introduced to England in 1917, again by the prolific George Forrest. These two species cross together readily and the resulting hybrids are called ‘Fabia Group’ hybrids.
Another rare species from China is Rhododendron fortunei, a striking large shrub or small tree that grows in colder parts of western China. The flowers are lilac.
Theodore Van Deen was a Dutchman, who, in 1926, started a nursery in Portland Oregon. Later, when his son Ted took over, and his daughter Kathy began to help, they turned the nursery into a major rhododendron producer called Crystal Springs Rhododendron Garden. Back perhaps in the 1930s, Theodore crossed together Rhododendron fortunei with plants of the Fabia group. The result? The amazing plant he named ‘Evening Grow’. Every plant has a story to tell.

Buying the Evening Glow Rhododendron at the Tree Center

Don’t limit your rhododendron collection to the ‘same old, same old’. Branch out and bask in the beauty and unique qualities of the Evening Glow Rhododendron. Let it transition your garden from late spring into early summer with its unique coloring, and grow something special – go on, give yourself a garden treat – you do the work, you deserve one.