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Species Rhododendron Descriptions By Name
R. macabeanum

Many have called this plant the “best of the big leaves.”  Its dark green, shiny, leathery leaves, some nearly a foot in length, always attract attention.  A yellow mid-rib adds to their appearance.  R. macabeanum comes from N.E. India (Manipur and Nagaland) and is a favorite in Scottish as well as Washington State gardens.  It can grow into a small tree, but is more likely to remain an impressive shrub in your garden, maybe 5 feet in 10 years.

R. macabeanum is one of the more compact and easy-to-grow big leaf plants, but would like some protection against extreme cold.  If you live in a colder region of our area, keep it in a large pot.  You can move it to a garage on the coldest winter days. It's hardy to 10°F.

R. macrophyllum

R. macrophyllum is that pink flower that grows in the woods of western Washington, gracing us with soft blooms in May.  It comes in lots of shades of pink as well as a much rarer white. R. macrophyllum is the only evergreen rhododendron native to the Northwest and is found mostly west of the Cascades in Washington State.


Once established, this rhody is remarkably drought tolerant, quite able to handle the dry months of our summer with only very occasional watering. Like all rhododendrons, R. macrophyllum is a light-seeker, meaning that in deep shade, this rhododendron will get leggy. Hence an open spot is probably best.

R. magniflorum

 R. magniflorum is perhaps best described as an R. glanduliferum on steroids. It boasts some of the largest flowers of the genus, adds fragrance and does it so late in the season that it's a miracle that the new growth hardens off in time for winter.


This is the first and perhaps the last time this species has been introduced  into Western gardens. With limited distribution in the wilds of China, the remnant population had an unfortunate location directly in the path of expanding agribusiness.

This is a plant on the large size - six feet or more in ten years. It seems to like a mix of sun and shade, and considering its first growth in September or so, an extra helping of fertilizer in July or August is probably a good idea. Hardiness does not seem to be an issue.

R. makinoi

The long, narrow leaves of this Japanese rhododendron (named after a Japanese botanist) give it a distinctive character. 


The young growth has a silvery indumentum on the upper leaf surface with a paler indumentum on the under surface.  The flowers are a soft shade of pink and the plant is well-behaved, reaching about six feet at the most. 

Moderate sun helps R. makinoi stay bushy and bloom more readily. It’s hardy to -10°F, -23°C.

R. mallotum

It’s hard to decide whether to grow this rhododendron for its flowers or for its leaves!  While the bright, red flowers make a spectacular show early in the season, the thick orange indumentum on the underside of the leaf gives a stunning effect all year long.  Put the two together and you have a truly remarkable species that has an all-round good look and feel! It comes from the border between Yunnan and Myanmar and is hardy to 5° Fahrenheit. It may reach four feet in ten years and will always reward with restrained dignity.

R. mallotum will appreciate a well drained soil.  It would like a mix of sun and shade as well as small amounts of fertilizer on Valentine’s Day and Mother’s Day.


R. megeratum

R. megeratum is an epiphyte that grows up in the trees (but does not feed off the tree). We found it in Arunachal Pradesh in the middle of a pile of orchids whose weight had caused them to come crashing down to the forest floor. It’s a dainty fellow – perhaps a foot to 18 inches tall with small glossy leaves and off white to yellow flowers. Perfect for the rock garden.

Since R. megeratum is an epiphyte, you might think of planting it on an old stump or working it into a wire basket on or in a tree. Think of it as an orchid instead of a rhododendron.


It prefers a mix of sun and shade with protection from the hot afternoon sun. Give it small amounts of fertilizer on Valentine’s Day and Mother’s Day. Gentle consistent watering keeps it happy. Most of all, good drainage with a loose, well-aerated medium is a must.

R. mekongense

Botanists are somewhat confused as to how to classify this little fellow, but gardeners know a winner when they grow one. R. mekongense is a deciduous to semi-deciduous species with bright yellow flowers that appear before the leaves, which are hairy at the edges which are sometimes tinged red. A broadly upright shrub, the plant will cover itself with flowers if given enough sun.

R, mekongense will like:


Partial sun to lots but don’t bake it;


Small amounts of fertilizer on Valentine’s Day and Mother’s Day together with gentle watering. It prefers loose organic soil with good drainage.

Expect three to four feet in ten years. Being deciduous, it is hardy to -5℉.

Even the pedicel of the flower is hairy.


It is native to Yunnan, NE Myanmar, S.E. Tibet, Nepal and Arunachal Pradesh. (It gets around).

R. micranthum

R. micranthum is in a class by itself. It is the only member of Subsection Micrantha mostly because of its unique flowers. They come in clusters of twenty or more small white flowers that resemble the flowers of the Subsection Ledum. It is a late bloomer with an abundance of bloom in June or July. It blooms at an early age.


R. micranthum has narrow leaves and can put out long shoots that can be headed back to keep it from becoming gangly as a youngster. You can expect four to five feet in 10 years. It’s hardy to -15°F, -26°C.


R. micranthum is one of those plants that, like many of us, get better with age. The long gangly shoots of youth calm down with age, and the plant forms a well-rounded bush. It responds well to pruning. Also like many of us, it develops more hardiness with age. It is widely scattered in China and it also grows in Korea as well. It blooms on terminal and axillary buds so it has side by side clusters of flowers. It’s a bit of a sleeper that deserves more attention. It invites my favorite question: “That’s a rhododendron?”


R. moupinense

This Chinese beauty will top out around three feet in height, but it packs lots of surprises – early flowers that are frost tolerant with pink and red tones; peeling red bark on a willowy plant and new growth that is truly a bronze delight.


This plant is part of a breeding program at Chimacum Woods to intensify the pink and red of the flower and is the result of the third generation of selection. 

R. moupinense is a choice dwarf that is very free flowering.  It dislikes a hot summer exposure but is quite drought resistant, doing well even near moisture greedy tree roots. It is an epiphyte, so it needs perfect drainage as it lives on a small root system. It is hardy to 0°F.

R. neriiflorum

This version of R.neriiflorum is the subspecies neriiflorum (as opposed to two other forms of R. neriiflorum which have minor variations – ah botanists). The tubular, bell-shaped flowers are thickly fleshy and a striking carmine red. There may be 5 to 12 flowers in a truss.

This neat, low-growing shrub may reach four feet in 10 years. It has been in our Western gardens since 1910 and always draws attention. Leaves have a whitish indumentum that adds interest. It likes a mix of sun and shade, but not the hot afternoon sun. This early mid-season bloomer is hardy to 5 degrees Fahrenheit.

R. nipponicum

R. nipponicum is a rare Japanese deciduous azalea from the island of Honshu, Japan.  It will have small white bell shaped flowers in early summer that will hang gracefully amidst the lush, soft foliage.


In the fall, the foliage will turn yellow.  The trunk will develop a smooth peeling deep brown bark with an interesting pattern noticeable in the winter.

R. nipponicum will appreciate small amounts of fertilizer on Valentine’s Day and Mother’s Day. It prefers mostly shade – the luxurious foliage will burn if the sun exposure is too strong. It needs good drainage with well-aerated soil. It may reach four feet in 10 years and is hardy to -5°F.


The deciduous Japanese azaleas are relatively unknown in the US, but they are an outstanding group of plants.  Truly unusual.

R. niveum

Here is the Smokey Joe of the rhody world – a wonderfully subdued bluish purple that draws people across the yard to see what you have blooming over there.  The whitish indumentum on the underside of the leaf only adds to the mystique.  The new growth has a whitish cast and the bud scales on the flower bud have a brown outline!  This is a well-behaved shrub that branches readily and may reach six feet in 10 years.

R. niveum will like a fairly sunny spot although some shade is necessary in the afternoon. Give it small amounts of fertilizer on Valentine’s Day and Mother’s Day. Good drainage as always please. It’s hardy to 5° F.

R. nudipes

R. nudipes is a rare Japanese deciduous azalea from Oki Island, Honshu, Japan.  It will have small rose purple flowers in early to mid spring that will pop out with the apple green rhombic foliage.  Later a second round of foliage will follow with leaves that look more like traditional azalea leaves.  In the fall, the foliage adds more interest by turning red, orange and yellow.

R. nudipes  appreciates some shade – the luxurious foliage will burn if the sun exposure is too strong, but heat does not seem to be a problem! It may reach three to six feet in ten years. 

The deciduous Japanese azaleas are relatively unknown in the US, but they are an outstanding group of plants.  Perhaps the best known isR. schlippenbachii, but R. albrechtii, R. sanctum and R. quinquefolium are all superb plants.  There are more, but each offers something unique for your garden.

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