Rhododendrons

Although many Rhododendrons cannot be grown in our climate, with thousands of varieties available, there are numerous Rhododendrons that have been bred to withstand the colder climates.  The gorgeous blooms put on quite a show in May and June, depending on the variety and boast flower colors of pink, red, white, yellow, and purple – one for just about every landscape situation.

It is often difficult to tell the difference between Azaleas and Rhododendron.   To botanists, they are all Rhododendrons, however gardeners like to distinguish between the two.  All Azaleas are rhododendrons but not all rhododendrons are azaleas which is why they do look so similar.  The best way to determine which one you are looking at is to remember that Azalea flowers have just 5 stamens while rhododendrons flowers can have 10 or more in each of their blossoms. And most Rhododendrons, although there are exceptions, have evergreen leaves.

Glen Echo stocks many of the PJM type Rhododendron.  This is a group of Rhododendrons that were named after early Rhododendron developer Peter J. Mezitt, and with the help of his son, they created a line of winter hardy Rhododendrons that are very popular today.

Rhododendron types are a bit fussy, but once you know these few preferences, they are easy to grow.  They enjoy environments where it is neither too hot nor too cold (Zones 5 to 8) which makes them a very good choice for our area.  Rhododendrons are called the ‘queens of the shade garden’ for good reason. They are flowering shrubs that grow quite happily in a shady location. When you are planting rhododendrons in zone 5, partial shade is fine and full shade is also possible. They like some sun, but if planted in an area with part-shade or dappled shade, they will excel.  Too much sun may scorch the leaves and dense shade can result in fewer flowers.

Zone 5 rhododendrons are also particular about soil. They thrive in moist, well-drained, acidic soils. Hardy rhododendron varieties prefer soil fairly high in organic matter and porous media. It’s wise to mix in topsoil, peat moss, compost, or sand before planting. Rhododendrons are shallow-rooted so take care not to plant too deeply. Protect from harsh winter winds and mulch annually. There should be little or no need to prune.

We stock quite a few varieties that will add color and charm to your garden.

Please check for current inventory as it can change quickly.

Bubblegum Rhododendron

This is a PJM-type Rhododendron that is noted for its single bubblegum pink flowers, red stems and small deep green leaves that turn bronze over winter adding more interest to the garden. It is a lightly scented, low, compact broadleaf evergreen shrub that typically grows to 3' tall and as wide. Makes a lovely hedge and is the perfect foreground for larger flowering shrubs. Flowers bloom in April.

Catawbiense Boursault Rhododendron

'Boursault' offers a spectacular display in spring featuring violet buds that open into lavender bell-shaped flowers with some reddish or pale brown spots. A dense, upright, evergreen rhododendron that will grow 6 feet tall in 10 years but eventually can grow to an impressive 10-15 feet tall. It is very cold hardy and heat tolerant. Beautiful as an accent plant, or massed in a border or informal hedge.

English Roseum Rhododendron

A sensational example of what a Rhododendron can display. Large, elegant trusses of showy rosy pink-purple flowers cover this shrub. The flowers stand out beautifully in contrast to the lustrous dark green foliage. It is a dense-growing evergreen shrub that thrives in cooler regions but benefits from protection against winter winds.

Haaga Rhododendron

Haaga Rhododendron is smothered in stunning clusters of lightly-scented shell pink trumpet-shaped flowers with pink centers at the ends of the branches in mid spring, which emerge from distinctive rose flower buds. It has green evergreen foliage. The narrow leaves remain green throughout the winter.

Helsinky University Rhododendron

Clusters of dark pink buds open to reveal stunning soft pink flowers. They feature a dark spotted pattern. An extremely hardy mid-sized rhododendron hybrid. It was the first of the Finnish hybrids, introduced in 1990, the University’s 350th anniversary which it is named after. Beautiful flowers cover the shrub about mid Spring.

Lee's Dark Purple Rhododendron

A hardy, compact evergreen shrub valued for its deep purple buds that open to large trusses of violet-purple flowers in mid-spring. Dark green leaves with wavy edges nicely frame the colorful spring flowers and provide evergreen interest year-round. Thrives in cooler regions with some protection from winter winds. A great foundation or accent plant.

Nova Zembla Rhododendron

One of the iron-clad rhododendrons, an informal name that indicates rhododendrons that are easy to grow and are hardy, even in cold climates. The flowers are bright red with darker spots that may fade to deep pink in bright sun and are up to 5 in. wide. Thick, glossy green leaves contrast nicely. It is an upright shrub growing 5 to 8 ft. tall and 5 to 6 ft. wide. '

Olga Mezitt Rhododendron

One of the hardier varieties, it is a vigorous grower with a spreading, upright habit and bears an abundance of showy, dome-shaped trusses of wavy, vibrant pink, lightly scented flowers beginning in late April. Shiny, green, lobed, recurved foliage turns a rich mahogany color in late fall, holding through winter. More heat and sun tolerant than other varieties.

PJM Compact Rhododendron

Stunning flowers emerge from distinctive fuchsia flower buds, then the compact shrub is draped in stunning clusters of lightly-scented lavender trumpet-shaped flowers with rose overtones at the ends of the branches in mid spring. Narrow, green evergreen foliage turns an outstanding purple in the fall, which persists throughout the winter.

PJM Elite Rhododendron

Very popular in our region, this Rhododendron is exceptionally cold hardy. When these large clusters of frilly, lavender flowers with slight hints of plum begin to show in late April, they are a very welcome sight. It is a dense plant and this prolific bloomer will put on a stunning floral display. The flowers are offset by glossy, dark green, elliptical foliage.

PJM Elite Star Rhododendron

Very compact, this floriferous, denser version of 'PJM Elite' will illuminate the landscape with huge clusters of deep lavender-pink trumpet flowers in late April and early May. This very hardy shrub is considered to be the most tolerant Rhododendron for cold conditions and will consistently deliver a breathtaking flower show each spring.

PJM Regal Rhododendron

This royal Rhododendron is a favourite amongst gardeners. Smothered in stunning clusters of lightly-scented dark lavender trumpet-shaped flowers at the ends of the branches in mid spring. It has handsome green evergreen foliage whose narrow leaves turn an outstanding mahogany in the fall, which persists throughout the winter.

Purple Gem Rhododendron

Love this colour! This outstanding shrub is covered in stunning clusters of lightly-scented purple trumpet-shaped flowers with violet streaks at the ends of the branches in mid spring. It has olive green evergreen foliage which emerges bluish-green in spring. The glossy narrow leaves turn an impressive coppery-bronze in the fall, which persists throughout the winter.

Purple Passion Rhododendron

A Rododendron that can take the shade better than some other varieties. This tough, evergreen shrub is covered in, deep reddish purple blooms highlighted with pink-white centres and delicate maroon spots appear in late spring to early summer. A beautiful contrast against glossy dark green, disease resistant foliage.

Purpureum Elegans Rhododendron

Super hardy and easy to grow, this plant performs flawlessly. A mid-sized broadleaf evergreen that suits all landscape applications. A vigorous, large, dense, broadleaf evergreen shrub that is valued for its large rounded clusters of rosy lavender flowers with white and yellow accents. A burgundy blotch in the upper lobe completes the drama.

Rimini Rhododendron

An incredible colour, this Rhododendron features glowing soft yellow to cream funnel shaped flowers edged in warm pink, and accented with yellow green spotting in late spring-early summer. A robust evergreen shrub that favours shade, it grows in a mound-like, hedging habit maturing to 3 feet high and 3 feet wide.

Roseum Elegans Rhododendron

A solid Rhododendron, prized for its large trusses of rose-lilac-colored flowers A vigorous-growing, medium-sized evergreen shrub that thrives in cooler regions but will appreciate protection from winter winds. An outstanding choice for foundation plantings or for use as an accent specimen.

Roseum Pink Rhododendron

A vigorous grower with good habit with large, glossy, dark green leaves. This large, dense, broadleaf evergreen rhododendron thrives in cooler regions. Its a popular cultivar valued for its large rounded clusters of rosy lavender flowers which can hold up to 20 attractive bell-shaped flowers with delicate dark pink dorsal spotting.

Share this article