JARS v50n2 - Pacific Northwest Rhododendron 'Improvers': Their Heritage and Progeny

Pacific Northwest Rhododendron 'Improvers': Their Heritage and Progeny
Some Observations With a Bias to North of the 47th Parallel
Clive L. Justice
Vancouver, British Columbia
Canada

Apart from those who grow and breed roses, the greatest "improvers" of garden shrubs are those legions of amateurs and professionals who tinker with that great genus of plants in the heather, or Ericaceae, family: the rhododendrons. This genus also includes the evergreen and deciduous azaleas. Japanese nurserymen and growers have been selecting, hybridizing and improving the evergreen Kurume azalea for over 600 years, and there are some thousand named and selected forms, some with different coloured flowers on the same plant. The Europeans and North Americans/Australians/New Zealanders didn't begin improvements to the rhododendrons and azaleas until the early and mid 1800s. In the Pacific Northwest improvement didn't begin until the 1920s and '30s, with the great bulk of their work occurring in the 1950s and '60s.

When David Don, botanist at Kew, classified and named Archibald Menzies' plant collection that included the Pacific rhododendron, Rhododendron macrophyllum , he had found at the head of Discovery Bay in Puget Sound, it was 50 years before 1848. That was the year when Joseph Hooker, son of Sir William, came back from plant collecting and exploring in the Himalayan foothills of Sikkim and northern India. Hooker brought back many rhododendrons with leaves, not 6-9 inches long as the Pacific rhododendron had but 12-30 inches long and up to half that in width. The flowers on these Himalayan plants were not the small light pink or dull mauve of R. macrophyllum but large, clear pink and crisp white trumpets and blood red, claret red and yellow bell shapes in trusses with double the number of individual flowers.

Since the epithet for big leaf, macrophyllum , had been used by Don for the Menzies' rhododendron discovery, Sir William had to give the rhododendrons that his son had collected epithets like grande and gigantea . He and his son also gave names like hodgsonii for R.H. Hodgson, British East India Company representative in Darjeeling who was Joseph Hooker's host while he stayed at this eastern Himalayan foothills station, and falconeri after a friend of both, who was Superintendent of Saharanpur Gardens in India, Sir Hugh Falconer. In R. dalhousiae they honoured Lord Dalhousie, the then Governor General of India. Fortunately for everyone the rhododendrons all performed and came up to the standards and expectations befitting their famous namesakes in this botanical old boys network.

With the Hookers of Kew there is and was some confusion as to who was who, William Joseph the father or Joseph Dalton the son. Both were close collaborators botanically, both were directors of Kew Gardens and both were knighted by Queen Victoria. Plants named by the father carry Hook , after the species epithet or variety name, while those named by the son, Sir Joseph, are designated Hook. fils . In 1850 the Himalayan rhododendrons that son Joseph discovered and whose seed he brought to Kew Gardens were described and illustrated by full-page colour lithographs in an elephant folio-sized book prepared by his father Sir William, then the director of Kew. This book did much to develop a keen interest in these magnificent plants and increased the anticipation and demand for them for use on the large estate gardens in Britain and Ireland. The Himalayan rhododendron species were also of great interest to the nurseryman for breeding with the smaller hardier eastern North American/Caucasus rhododendrons to create new hardier hybrids with a wider range of flower colours, particularly pure reds and scarlets. Most hybrid rhododendrons at this time had the mauve, purple and pastel flowers of R. catawbiense , R. maximum , R. ponticum or R. caucasicum .

This was a time before field or salon photography, either colour or black and white, with the knowledge that it would be 10 or 15 years before the rhododendrons would produce bloom. As a "coffee table" book of magnificent size with full coloured drawings on every page, Rhododendrons of the Sikkim-Himalayas held centre stage for the two decades before these magnificent plants bloomed. It was a further decade or more before there were hybrids or species plants available for gardens. These rhododendrons didn't reach the gardens of the Pacific Northwest until the second and third decades that followed World War I.

One of the earliest crossings, made sometime before 1870, used Joseph Hooker's R. griffithianum to produce a hybrid the English nursery of Standish & Noble introduced and named 'Cynthia'. With rosy crimson conical trusses of flowers and a strong and hardy constitution, 'Cynthia' and several other English rhododendron hybrids called the "Ironclads" (they were supposedly hardy to -15°F), made their way to the Boston, Cape Cod and Long Island estate gardens in the first decade of this century. 'Cynthia' arrived in the Pacific Northwest sometime in the 1920s. The milder climate of the Pacific Northwest permitted 'Cynthia' to be planted as a single front lawn specimen in many Vancouver, Victoria, Seattle, Tacoma and Portland gardens. You still can see proud examples of this Victorian/Edwardian style of garden involving the display of specimen plants in isolated and lone splendour surrounded by a closely mown sward.

Over the years gardening and home landscape styles have changed, and plants in the lawn were moved up against the wall of the house to become the vogue called foundation planting or the new fashion in the '80s and '90s where plants are moved out to the lot perimeter. When town and row houses pushed out to the sidewalk replacing the detached house with the front garden, many of these plants of 'Cynthia' that survived along with a few of 'Roseum Elegans' similarly displayed were moved into parks or larger gardens. In 1950 two 40-year-old plants of 'Cynthia' were moved from gardens in Portland into the American Rhododendron Society test garden in a Portland park. When Ted Van Veen pictured these two rhododendrons in his 1969 book Rhododendrons in America , the plants had reached a height of 20 feet and together had a spread of 30 feet for a truly magnificent show of thousands of blossoms each year in May. In 1922 George Fraser, rhododendron nurseryman of Ucluelet, B.C., planted a 'Cynthia' in the yard of the Tofino Anglican Church. Fifty-five years later in 1977 when the writer photographed the Tofino 'Cynthia' it measured 25 feet in height and had an 8 inch diameter trunk. The rhododendron hybrid 'Cynthia' (Greek goddess and sister of Apollo), born over 125 years, ago is still the becoming and performing plant that the name evokes (4).

The Himalayan species R. griffithianum was named by Hooker for William Griffith, superintendent of the Calcutta Botanical Gardens. It also became the basis for a group of magnificently flowered, white to pink fragrant rhododendron hybrids developed in England by Lord Loder. Called the Loderi Group, it includes names for individual selections like 'Loderi Venus' (pink) and 'Loderi King George' (flesh pink). 'Beauty of Littleworth' (white with purple blotch) also has R. griffithianum in its parentage. The name was the title of the estate next door to the Lord Loder's spread, Leonardslee. These rhododendrons grew to 15 to 20 feet in no time with 9-12 inch high trusses of 4 inch diameter flowers that soon set the style and standard for the late Victorian and Edwardian large suburban Surrey, Hampshire, Devon, Somerset and Cornwall country gardens. These magnificent plants proved to be a bit too tender and too large and sprawly for the smaller Pacific Northwest suburban garden. However, they were used extensively for hybridising in the Pacific Northwest to produce hybrids more suited to our local climate and gardens.

The Washington Park Arboretum in Seattle, an Olmstedian landscape, has a fine collection of these Loderi's. Planted by Brian Mulligan in the 1950s, some are now over 20 feet in height and spread 40 years after their introduction (3). Rhododendron griffithianum is perhaps the most important of the Sikkim rhododendrons to Pacific Northwest gardens that Joseph Hooker collected. Through the Loderi's it became a major part of the gene pool for the Pacific Northwest's large-leaf, large flowered rhododendrons exemplified in the Walloper* Group that includes the cultivar 'Point Defiance' (named for a large park in Tacoma, Wash.), made by Alaska fisherman turned hybridizer, Halfdan Lem. It has over 50 percent griffithianum genes through its complex development from 'Beauty of Littleworth' to 'Norman Gill' and 'The Honourable Jean Marie de Montague' to 'Marinus Koster'. All of these great hybrids that originated in England have R. griffithianum as a parent.

One of the Pacific Northwest's most popular rhododendrons for landscape use is the hybrid 'Unique', bred in England in the early 1930s. Part of the heritage of this early blooming shrub, with flowers of cream with a touch of pink and compact medium crisp foliage, is the species R. campylocarpum . Joseph Hooker also found this fine yellow/white flowered rhododendron in the Sikkim Himalayas. Although it has the quality to go directly into the garden, the Sikkim species has proved tender in the Pacific Northwest. Its progeny 'Unique', though, is completely at home in gardens from Eugene, Ore., to Comox, B.C. 'Unique' does much better in full sun than in shaded areas of the garden.

Another campylocarpum hybrid (the epithet means bent fruit) is 'Moonstone' (now known as the Moonstone Group). It's a product of a cross with a rhododendron species from China that has the species epithet williamsianum . This is the most highly rated and beloved of all rhododendron species having small, shiny, heart-shaped, cordate green leaves, bronze new growth and pink bell-shaped flowers. This species grows in full sun forming mounds of shiny green foliage. Rhododendron williamsianum was found and seed of it collected by the greatest of all the plant hunters, the horticulturist Ernest Henry Wilson. He found this fine plant in 1908 growing individually on cliffs and in heath/moor-like communities in China's Sichuan Province. In the Pacific Northwest R. williamsianum is a species that needs no improvements to make a fine garden plant.
The two species, Hooker's campylocarpum and Wilson's williamsianum , were crossed and produced 'Moonstone' in England in 1933. It is a compact grower to 4 feet with shiny green heart-shaped leaves and light yellow bell-shaped flowers. A rhododendron with a similar meeting of the two species through the Loder route and bred in the Pacific Northwest by Roy Clark of Olympia, Wash., was 'Olympic Lady ' (now known as Olympic Lady Group). It is taller growing with larger leaves than the Moonstone Group and the flowers, more campylocarpum-like , are pink fading white and are larger than the light yellow bells of the Moonstone Group. Both go well together and are accommodating to the smaller Pacific Northwest gardens.

The most widely known williamsianum improvement for beauty of flower and foliage is 'Bow Bells'. It was produced in England in 1933 but didn't start to be used in Pacific Northwest garden landscaping until the 1950s. A low growing mound reaching 3 to 4 feet in height with an equal spread, 'Bow Bells' likes full sun situations in Vancouver and Vancouver Island gardens, while dappled shade suits it best for gardens in Portland and south. Harold Greer describes 'Bow Bells' qualities best: "In blossom 'Bow Bells' is a perfect mound of luscious pink flowers appearing first as deep pink buds, contrasting with the opened flowers giving a two-toned effect. The flowers are followed by shiny copper new leaves appearing at every stem tip. A display by itself! The season changes, and day by day the mound becomes a superb jade green with rose red bud scales" (2).

The biggest, boldest, brightest and "bestest" of the Pacific Northwest rhododendron originations is 'Anna Rose Whitney'. Named for the mother of the hybridizer W.E. (Bill) Whitney of Hood Canal and Camas, Wash., it was introduced in 1954. 'Anna Rose Whitney' has a good measure of Hooker's griffithianum blood from one of the parents 'Countess of Derby' to give it large stocky form, thick heavy foliage and large strong dark pink flowers. Its quality and character make 'Anna Rose Whitney' recognizable anywhere. During the 1986 Congress of the International Federation of Landscape Architects held in Osaka, Japan, we found an extensive planting of 'Anna Rose Whitney' at a mountain top forest interpretation centre in a forest reserve high above the city of Osaka. Its large dark green slightly crinkled leaf is an unmistakable identifying characteristic.

The late Bill Whitney scored with another great hybrid for the Pacific Northwest. This superb large foliage, large growing rhododendron he named 'Virginia Richards'. The flowers are large, frilled and peachy pink. 'Virginia Richards' is a very complex hybrid, but the flowers of griffithianum and the foliage of campylocarpum come through strongly. With its parentage, 'Virginia Richards' will certainly reach tree proportions in 20 to 30 years. This jewel of a plant was introduced into the British Columbia coastal and Fraser Valley gardens by the late jeweler/rhododendron collector-connoisseur, Ed Trayling of Surrey, B.C.

H.L. Larson of Tacoma hybridized rhododendrons with griffithianum genes to produce the red flowered hybrid he named 'Malahat'. The name honours a Vancouver Island tribe of Pacific Northwest Indian peoples. They also have a mountain on lower Vancouver Island named for them.

"A clean and well mannered habit" is Harold Greer's short description of 'Haida Gold'. It is a fine yellow flowered rhododendron grown by Dr. Bob Rhodes of Gabriola Island, B.C., with a name that honours the Queen Charlotte Island's native people, the Haida (2). It has some of the genes of campylocarpum through 'Goldsworth Yellow', an English hybrid, and R. wardii , a species collected by and named for Mr. Plant Explorer himself: Frank Kingdon Ward. He was also a fine writer of 20 books on his plant collecting trips over some 40 years in Western China, Tibet, Northern India and Burma. Kingdon Ward's most popular and widely grown plant introduction is the Tibetan blue poppy, Mecanopsis betonicifolia .

The hybrid 'Seattle Gold' is a fine yellow flowered hybrid with campylocarpum genes developed by Halfdan Lem of Seattle. It was introduced by Donald McClure of Seattle. 'Seattle Gold' is a tall growing, strong long leafed shrub that can stand alone as a specimen or, for instance, in the company of two rhododendrons named for ladies: a 100-year-old hybrid 'Lady Grey Egerton' or the more recent hybrid of 70 years named for the wife of Canada's sixteenth Governor General, 'Countess of Athlone'. Both have mauve flowers and an elegant open habit that blend in leaf and contrast in colour with 'Seattle Gold'.

Another great Pacific Northwest peachy yellow flowered rhododendron with a good stock of genes from Hooker's griffithianum and an all-around great plant for the garden is 'Butter Brickle'. Jack Lofthouse of Vancouver, B.C., originated this floriferous, compact growing shrub that has flowers that appear double as the outer leaves or calyx forms an overskirt about the base of the individual flower. This apron has the same pink and yellow as the flower. Most likely 'Butter Brickle' gets this flower feature from the species R. dichroanthum . It was found in 1907 by another great collector of plants, George Forrest, who worked exclusively in Western China. George Forrest made seven expeditions there to collect seed of rhododendrons for nurseries and private gardens over the period 1907 to 1932. He found R. dichroanthum on the Tali Range in western Yunnan Province.

On a later expedition in 1917 George Forrest found R. griersonianum in the Shweli-Salwin Divide in western Yunnan Province. When raised in England R. griersonianum was too tender a plant for all but the most mild of English gardens, but to the hybridizer and nurseryman the pure red flower (it had no hint of blue pigment) provided the genes for a great number of hardy red flowered hybrids. One of the best is named 'Elizabeth' for Queen Mother Elizabeth and introduced to English gardens just before World War II in 1939. In 1954 this fine low growing rhododendron was introduced into British Columbia coastal gardens by Len Living, a nurseryman/landscape contractor of Richmond, B.C. 'Elizabeth' is vigorous and floriferous with pure red trumpet flowers that cover the plant in early May. This rhododendron looks good in the garden when backed up with the variegated leafed dogwood shrub cultivar 'Creamedge' and the evergreen Pieris 'Forest Flame' with red new growth.

The bicentennial of Vancouver and Menzies' voyage to Pacific Northwest waters occurred in 1992. This year was also the centennial of the founding of Burnaby, B.C., the community that shares Burrard Peninsula with the City of Vancouver. As the rhododendron is the official flower of Burnaby, to honour this occasion the Burnaby Beautification Commission held a competition to select a rhododendron hybrid that would be suitable for the parks and gardens of Burnaby and to carry the name 'Burnaby Centennial'. The rhododendron that won the name was hybridized by E.J. Trayling and raised by Vern Finley, a collector and amateur breeder of rhododendrons in Surrey, B.C. 'Burnaby Centennial' is a mid May bloomer with a strong tight truss of large red flowers and good sized leaves. It is a strong and vigorous grower and, yes, it does have some genes from Hooker's collecting in Sikkim 150 years ago. 'Burnaby Centennial' looks to be every bit as vigorous and accommodating to garden with a striated dark pink flower which suits the plant. Rhododendron yakushimanum has also supplied genes along with another species, R. pseudochrysanthum , to produce the hybrid 'Golfer' with indumented foliage and pink flowers. 'Golfer' was developed, named and introduced by Warren Berg, rhododendron collector and hybridizer of Port Ludlow, located on Hood Canal (named after Capt. Vancouver) on the west side of Washington State's Olympic Peninsula. In 1984, the late Milton Wildfong, rhododendron hybridizer and nurseryman of Mission in the upper end of British Columbia's Lower Fraser Valley, developed and registered a complex hybrid rhododendron he named 'Ruffles and Frills'. It is a 4- to 6-foot plant with heavily textured leaves that last for three years and are bronzey when young. The fragrant frilled flower, yellow on the inside, pink on the outside, 12 in a flower truss, ties together in its makeup the three eras of rhododendron development. The heritage of 'Ruffles and Frills' includes the Victorian, R. griffithianum , the Edwardian, R. griersonianum , and the modern R. yakushimanum . 'Ruffles and Frills' is not unique in this regard, as there are many new rhododendron hybrids that have this century and a half of linkage with the species from the slopes of the Sikkim Himalayas, the gorges of China's rivers and the islands of Japan.

A Northwest rhododendron that is a beautiful native deciduous shrub is called the western azalea, or R. occidentale . In the past this fine flowering plant has played a large and significant role in England in the breeding and development of the big intense coloured hybrid deciduous shrubs. First out were the Knap Hill azaleas. In 1870 Anthony Waterer of Knap Hill Nursery of Woking, England, began hybridizing and developed hybrids of the deciduous rhododendrons that included hybrids from Belgium and species from eastern North America, China, Asia Minor along with R. occidentale from western North America. Then in the 1920s these were hybridized further by Lionel Rothschild to produce the Exbury strain of azaleas with flowers that are bigger, more intense and with a wider range of reds, oranges, salmons, apricots, yellows, pinks and whites and combinations of these colours under such names as 'Oxydol' (whitest white), 'Honeysuckle' (flesh pink with orange flare), 'George Reynolds' (brilliant buttery yellow), 'Klondyke' (glowing gold), 'Clarice' (pale salmon with orange patch), 'Hotspur Orange' (orange red), and 'Scarlet Pimpernel' (obviously red). There were and are still many more names of these big and many coloured, strong growing hybrids grouped under the names of the English nurseries that produced them, Slocock, Windsor, etc. These were not released for garden use in England until about 1924, and did not reach the Pacific Northwest until the late 1940s. In the Pacific Northwest, the Bovees Nursery of Portland and amateur enthusiasts Arthur Wright, Howard Slonecker, the late Eric Langton of Maple Ridge, B.C., and Jock Brydon carried on improving the flower size and colours of this complex group of deciduous shrubs. No better modern written coverage of all the rhododendron species and hybrids commonly called azaleas is to be had than that found in Fred Galle's book Azaleas . (1). Locally selections of the deciduous azaleas are grown from seed, and improvements to flower size and colour are selected and raised by cutting propagation for the market. These azaleas have been selected and bred almost exclusively by amateur rhododendron enthusiasts, and they give an even wider range of colours to grow in Pacific Coast gardens (1). The seedlings raised from the native species, itself a fine garden plant, are also a part of this rich feast of available colour and variety. Because these azaleas lose their leaves annually they go out in a burst of colour to provide a second season of display in autumn when the leaves turn red, yellow, gold and rust, sometimes equaling the flower display of spring. Stan Sorenson of Abbotsford, B.C., has originated a deciduous azalea with huge yellow flowers he named 'Cheerful Giant' along with one with rosy pink blooms that has a red "eye" that is aptly named 'Stan's Tutti-Frutti'*. Both these deciduous azaleas are available. In the garden deciduous azaleas prefer full sun, good well drained garden soil with plenty of moisture and should be planted in communities with evergreen shrubs like lily of the valley shrub, kalmia, tall mahonia, the deciduous cream edge dogwood shrub and the lace cap hydrangeas.

Pacific Northwest selection and introduction of the native forms, variations and hybrids of the western azalea R. occidentale has been going on for less than a generation. It was begun by Washingtonians Leonard F. Frisbie of Tacoma, Ben Lancaster of Camas and carried on by Frank D. Mossman of Vancouver and Britt Smith of Kent. A number of these western azaleas selections are now available for Pacific Northwest gardens. A sample: 'Crescent City Gold'* (white with gold stripes), 'Humboldt Peppermint'* (white with pink stripes), 'Leonard Frisbie' (red with orange flare), 'Rogue River Belle' * (white, pink markings, yellow blotch), 'Sacajewa' (pronounced Sac-a-je-wa; orange tinted pink). This last name honours the Indian woman translator/guide to the Lewis and Clark Expedition that came down the Columbia River to the Pacific Ocean in 1805. Thirteen years earlier Master William Broughton on the ship Chatham charted both sides of the Columbia from the mouth to the Willamette River. He named what is now Hayden Island "Menzies Island" after the Surgeon Botanist Archibald Menzies, who had he been on board would have added R. occidentale to his list of first Pacific Northwest plant discoveries. As Vancouver's ship Discovery with Menzies aboard unfortunately could not make it over the bar at Columbia's mouth it proceeded to San Francisco to wait for Broughton to catch up.

References
1.  Galle, F.C. Azaleas. Portland, OR: Timber Press; 1985.

2.  Greer, H.E. Greer's guidebook to available rhododendron species & hybrids, second edition. Eugene, OR: Offshoot Publications; 1988.

3.  Mulligan, B.O. Woody plants in the University of Washington Arboretum Washington Park. Seattle, WA: University of Washington, College of Forest Resources; 1977.

4.  Van Veen, T. Rhododendrons in America. Portland, OR: Sweeney, Krist & Dimm, Inc.; 1969.

* Name not registered.

Clive Justice, founding member and Life Member of the Vancouver Chapter, is a retired landscape architect, park and display garden planner and government advisor.