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Journal American Rhododendron Society

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Volume 59, Number 1
Winter 2005

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Fifty Years of Testing and Breeding Rhododendrons in Nova Scotia
Donald L. Craig
Centreville, Nova Scotia
Canada

A permanent printed record of the history of the Kentville Research Station's rhododendron breeding programme does not exist. As I am the only one that has the information I hope that this article will document its beginning in 1952 and step by step development up to my retirement in 1983. Over time our project revealed much new information about the diversity of the genus Rhododendron - its forms, habits, adaptability and great spectrum of colour. The endorsement of our work by the public and media was a source of inspiration. I hope that this report will be useful to the home gardener and anyone contemplating a similar programme, be it large or small. John Weagle's very generous contribution to the organization and presentation of this article is acknowledged with sincere thanks. Don L. Craig

        Nova Scotia is a 544 km. long, 80 km. wide peninsula between the 43rd and 47th degree north latitudes. It is surrounded by the Atlantic Ocean and barely joined to New Brunswick and the rest of North America by a narrow isthmus. Kentville is located in the agriculturally rich Annapolis Valley, which is approximately 100 km. long and 16 km. wide. The south and north mountains running west to east protect the Valley creating a pocket where tree fruits, berry crops and ornamentals thrive. The Bay of Fundy, 16 km. to the north, modifies the climate. Halifax, the provincial capital, is 107 km. east of Kentville on the Atlantic coast and has quite a different climate.
        The Valley is in Plant Hardiness Zone 5b, the extreme western end of Nova Scotia and much of the coast Zone 6a, southern coastal area 6b (with a few parts perhaps even 7a or better) and the interior 5a. Weather data for Kentville for a 10-year period shows a minimum low of -23°C (-9°F), which occurred once in December, -24°C (-11°F) once in January, -27°C (-17°'F) once in February and -20°C (-4°F) once in March. Winter temperatures can fluctuate from a low of -18°'C (0°F) to above freezing in a 24-hour period. The climate is strictly maritime - snow, rain, wind, frost and moderate temperatures which can shift rapidly in winter. The Valley is considerably hotter and drier than coastal areas but can boast good deep soil.

The Beginning: What is the KRS?
In the beginning there were no plans to do anything more than make the vista more presentable when approaching the Kentville Research Station building complex. The approach to this view was over a pond and its large weeping willow. The banking behind the pond faces north forming a semi-amphitheater some 30 meters high and 120 meters long. The banking was a mess of brambles and weed trees which when removed brought order out of chaos. The only gem was an old but small planting of "iron-clad" rhododendrons (probably planted around 1920). They had grown well so the obvious was to plant more. Thus the search for plant material and knowledge had begun. We were starting from scratch.

Securing Plants
The first attempt to secure plants took 200 cuttings from the Station's "iron-clads" and to my surprise most of them rooted. In due time a listing of rhododendron species seed available from the Sweden's Göteborg Botanical Garden came to my attention. At this point, it dawned on me that this could serve as a starting point for a collection of species and cultivars. In April 1953 we received seed of species from B. Lindquist at Göteborg who had just returned from Northern Japan, this thanks to our connection Dr. I. Granhall at the Balsgĺrd Fruit Institute in Fjälkestad, Sweden. Presumably a few were collected in Northern Japan: RR. concinnum, fargesii (now R. oreodoxa var. fargesii), fauriei (now R. brachycarpum ssp. fauriei), fauriei var. rufescens (now R. brachycarpum ssp. brachycarpum), ferrugineum, flavum (now R. aureum), hippophaeoides, hirsutum, insigne, intermedium, longesquamatum, luteum, ponticum, schlippenbachii, searsiae, smirnowii, tschonoskii, vaseyi and viscosum (as well as a R. catawbiense hybrid, Gladiolus primulinus, G. palustris and Chrysanthemum cinearifolium). And so we proceeded to produce plants. In terms of winter survival and plant quality R. fauriei and R. schlippenbachii were by far the best performers. Summer heat was a limiting factor for some while winter cold probably got the others. From then on we made many contacts for plants and information. The search extended to four nurseries on the U.S. West Coast including Greer Gardens in Eugene, Oregon, Van Veen's and Bovee's nurseries in Portland, Oregon. On the East Coast we procured plants from Shamarello & Sons, Euclid, Ohio, Warren Baldsieffen in New Jersey, Tingle Nursery, Maryland, and David Leach in Pennsylvania. In England the Knaphill Nursery, Surrey, and the Goldsworth Nursery on Woking supplied material. In Sweden the Göteborg Botanical Garden and in Canada Woodland Nursery, Mississauga, Ontario, and later Bayport Plant Farm in Bayport, Nova Scotia, topped off the collection. The core of the Research Station's plantings came from these sources and, with the exception of most of the species from Sweden, the survival rate and plant performance of most plants from these sources was very satisfactory. By 1955, 42 beds had been prepared and planted, by 1957, 545 rhododendrons and azaleas were in permanent positions, and by 1975, 50 beds contained 1,000 rhododendrons and azaleas.

My Position
My position at the Research Station was that of a research scientist heading up the "Crop Section," which included ornamentals. My specific task was to develop a research programme for berry crops. Two years of graduate studies at the University of New Hampshire provided an opportunity to specialize in plant breeding. I am still involved in plant breeding as a hobby.

Why a Programme
Once involved with the initial Kentville rhododendron plantings, I had an opportunity over time to visit many of the world famous rhododendron gardens. My journeys took me from Seleger's Moor in Adliswil, Switzerland, to the Dunedin Botanical Garden in New Zealand. Points in between included Kew, Exbury, Great Windsor Park, Savill, Wisely and Stourhead all in England. A year's doctorate work transfer to the Scottish Horticultural Research Institute in Dundee in 1963 enabled me to roam at will from the Cox garden at Glencarse to Inverewe in the northwest with Brodick Castle, Crathes and Sherriffs in between. Of course the Edinburgh Botanical Garden was revisited several times. The Bodnant Garden in Wales was wonderful. In the United States my visits included numerous East Coast, West Coast and Virginia gardens. In Canada, Vineland, Ontario and British Columbia beckoned me several times.
        I pursued the Kentville programme because I wanted others to see and learn about these wonderful plants that I was privileged to see in so many of the world's best gardens. Each garden visited was an invitation for me to come back to Kentville and attempt to improve the plantings. Sufficient money and labour were in the end critical factors that could not be overcome.

George Swain
The rhododendron programme initiated in 1952 was nicely underway when the late George Swain joined the Station's staff in 1957. It was his gift of plant knowledge and landscaping that was mainly responsible for the numerous plantings, which became the Station's showpieces. The collaborative breeding of Swain and Craig produced 14 cultivars.

George Swain with 1958 Kentville crosses
George Swain with 1958 Kentville crosses.
Photo by Dick Steele in 1966

        Swain resigned in 1967, the year of the Station's first Rhododendron Sunday. The rhododendron project reverted to my care and the tradition of having a Rhododendron Sunday has continued.
        A conservative estimate of the number of people that viewed the plantings from 1967 to 1983 was in excess of 100,000.
        The success of the Station in determining the adaptability and suitability of many rhododendron cultivars and species was a factor in the decision made in 1972 to form the Rhododendron Society of Canada. By 1977 the Atlantic Chapter was formed by founding members Barbara Hall, Aileen Meagher, Walter Ostrom, Dick Steele, George Swain, John Weagle and myself and now numbers well over 200 members. Rhododendron Sunday created a surge in rhododendron plantings about the province. If success can be measured in awards, there can be no doubt about the achievements of the Station which prior to my retirement in 1983 accumulated 16 major and 200 first, second and third class ribbons at national and regional flower shows. The popularity of rhododendrons in the province still climbs to this day and the wide range of cultivars available in the province is astounding.

Steele, Pike and Hancock
For many years Dick Steele, acknowledged as Canada's foremost rhododendron and azalea authority, has very generously given of his talents and knowledge of rhododendrons through the regional and national societies and through public speaking, radio, TV and the media. His firm belief in so doing is that the world can be a more beautiful world for humanity if more people can be encouraged to become involved in the culture of ornamental plants. To this end, the Kentville Research Station, my own garden and those of many others have been the beneficiary of his philosophy and generosity.
        During the 1953 to 1983 period the Kentville plantings progressed from a small to a large collection of display beds containing some 1,000 rhododendrons and azaleas. In addition to assisting in this part of the programme he encouraged and assisted the breeding programme with planting material, pollen, knowledge and advice.
        Capt. Steele's contributions helped in making the Kentville plantings a major attraction for the public. The display of many cultivars and species became the largest in Eastern Canada affording the public an opportunity to see at first hand the diversity of plant form, flower and foliage quality and color.

Dick Steele, Don Craig, Robert Seleger
Dick Steele, Don Craig, Robert Seleger.
Photo courtesy of Don Craig

Radcliffe Pike
Another notable contributor to the Kentville programme was the late Radcliffe Pike of Lubec, Maine, whom I met in 1951 at the University of New Hampshire graduate school. His knowledge of plants was amazing and his enthusiasm knew no bounds. I am certain that much of my enthusiasm for rhododendrons came via Rad.
        I recall memorable trips with Rad to the Arnold Arboretum at Jamaica Plains, Massachusetts, and to the Reefe Point Garden in Bar Harbor. It was at Reefe Point that I was to view the hardiest and best R. fortunei specimen that he knew. Rad crossed this fortunei with a superior selection of R. smirnowii. Pike's records of the New Hampshire rhododendron and azalea breeding programme state that this smirnowii came via "Reefe Point Gardens, Bar Harbour, Maine. Second generation in Maine from plants from Edinburgh Botanic Gardens, Edinburgh Scotland. The fortunei from seed from Edinburgh Botanic Gardens." At a later date Rad sent a number of the seedlings of his fortunei x smirnowii cross to Kentville where they developed into very large and beautiful showpieces.

Leslie Hancock
The late Leslie Hancock of Mississauga, Ontario, the very well-known nurseryman and plant breeder, was also a wonderful supporter of the Kentville programme. Like Pike, he was a book of plant knowledge and acknowledged as one of Canada's foremost rhododendron authorities. Through his tireless efforts, the Rhododendron Society of Canada came into being in 1972. It was indeed an honour to have been asked to serve as a founding director of the Canadian Society and to serve as President (1984-85).
        Leslie sent many plants to Kentville including seedlings from R. fortunei crossed with R. smirnowii. They were planted with the Pike plants where they have performed wonderfully well.

Cultivar Testing and Breeding
I firmly believe that cultivar evaluation is absolutely necessary as an adjunct to breeding for improvement. In the Research Station strawberry breeding programme (1952-83) many cultivars were evaluated. We made many crosses utilizing cultivars from Germany, England, New York State, State of California, and Canada for their desirable genetic traits, as well as the wide genetic base they provided. Thousands of seedlings were fruited from which eight outstanding selections were chosen for naming and release. Their acceptance has been phenomenal.
        Using the same approach for rhododendrons we had by 1975 evaluated 81 species and 170 rhododendron and azalea cultivars. "Evaluation" means a yearly rating of winter hardiness, bloom date, colour, plant and flower quality. We used the hardiness rating system developed by the American Rhododendron Society System where H1 is hardy to -32°C (-26°F), H2 to -26°C (-15°F), H3 to -21°C (-6°F). By 1983, 234 parental combinations had been made, 15,500 seedlings produced and flowered, 94 selections made and 14 of the 94 named and registered.
        The breeding philosophy was the same as that used for the strawberry, mainly that a relatively small number (approx. 100) of seedlings will reveal the value of a specific cross. Parents vary greatly in how well they combine with one another. It is called "specific combining ability." If they combine well the cross can be repeated on a larger scale; many selections have been made from 100 to 200 seedlings or less. Superior parental appearance does not guarantee superior combining ability. Parents must be tested first.
        Over the years many of the Kentville seedlings were grown in the Station's fields where they were exposed to all of the weather stresses such as wind, cold, no shade and no irrigation. Some were also grown in ground beds, others in ground beds under a lath shade canopy. With the exception of the very early crosses, which were made in a glasshouse, crosses were made on plants growing outdoors.

First Crosses Made 1958
That Swain and I should become involved in a rhododendron-breeding programme was inevitable. George had success in breeding commercial snapdragons in Ontario and I was fresh from graduate school where the University of New Hampshire Department of Horticulture was strongly focused on plant breeding. I was also very much involved with Kentville's strawberry and red raspberry breeding programme.
        Swain made the first crosses in 1958. Parents involved were 'Doctor H.C. Dresselhuys', R. smirnowii and R. catawbiense 'Catalgla'. Inter-crossing the three in a glasshouse with their reciprocals produced 537 seedlings. These seedlings were grown in an open station field fully exposed to the elements. They grew well, flowered and were all pink, as one would expect. They were also very winter hardy. Fifteen were selected and one was named 'Gabriel' ('Doctor H.C. Dresselhuys' by R. smirnowii). Several were sent to the Fredericton, N.B. Research Station (Zone 5A) where they performed very well in that very cold climate.
        After this first year of crossing we set out our breeding objectives which were to produce rhododendrons sufficiently hardy for the colder regions of Atlantic Canada compact enough to be useful for landscaping modern homes, a good range of flower colors, and early, mid and late season flowering. Tolerance to mildew infection was a criterion for azaleas. Many of the azalea cultivars now available are mildew susceptible while others are not. We crossed tolerant cultivars and had good results in terms of producing tolerant seedlings. "Generous in saving, quick to discard" is a breeding mantra which should be recited daily by the aspiring breeder.

My Favorite Kentville Cultivar
You might ask me to name my favorite Kentville bred rhododendron. Without question it is 'Minas Peace'. 'Minas Peace' was entered as a numbered seedling in the Canadian Society 1976 Montreal flower show. The plant is semi-compact, leaves dark green, leaf underside covered with thick grey-orange indumentum, flower buds rosy red opening to white suffused pink with light rose stripes on the back of the corolla, flower quality superb, compact trusses born above the foliage. If there were no flowers it would still be worth growing because of its form and foliar quality. 'Minas Peace' is more comfortable in Zone 6 than 5B. It was judged "Best" in the Montreal show.
        The first cultivars released received their names from Longfellow's poem "Evangeline." The poem tells the story of the 1755 expulsion of the French Acadians from the Grand Pré area some 16 km. east of Kentville. The 3000 Acadians were herded onto British sailing ships; 900 homesteads in Grand Pré alone burnt to the ground. They sailed out of the tidal Minas Basin, which is part of the Bay of Fundy and only a short distance from Grand Pré. They were dispersed from New England to the West Indies. The most fortunate were put off at Louisiana where they were welcomed by their own race. There were only a few names in the poem so to keep the historical connection the prefix 'Minas' was used. Minas was a community not far from Grand Pré.

Rhododendron luteum
Rhododendron luteum is a highly desirable deciduous azalea species. Its yellow tubular/funnel-shaped, long-lasting flowers have an exquisite sweet fragrance which permeates the whole garden. Hailing from the Caucasus, Turkey, and several rather nearby areas it is no surprise that the experience of RSCAR members is that many luteums are not terribly winter hardy including most wild collected seed and the Rhododendron Species Foundation's named cultivar 'Golden Comet'. Our good fortune was that Nova Scotia hardy luteums came from the Lindquist seed received in 1953. Twenty-five seedlings were produced. A few were planted along the top of the north facing banking in the pond area. Being over-shadowed they nonetheless flowered regularly but not well. Three more were planted in a small bed fully exposed on the crest of the hill leading to the picnic grounds; these flowered well but one was outstanding in flowering, growth, vigour, plant quality and both bud and stem hardiness. And so this "outstanding luteum" was a very valuable addition to Nova Scotia gardens. A few years ago seed of these good luteums were sent to the RSCAR Seed Exchange and hopefully they have grown and flowered as well as those in my own garden. I cannot comment on the fate of all twenty-five original seedlings: the time lapse of 50 years is the culprit.

A 'Fundy' - 'Bellefontaine' Cultivar Comparison
The KRS cultivars 'Fundy ' and 'Bellefontaine' were derived from the same cross and so it is not surprising that they are similar in general appearance. Members who have lost labels can easily confuse the two. Here are a few distinguishing characteristics. Twenty-five to thirty year-old plants of both cultivars have reached a height of nearly 5 meters at the KRS and elsewhere. Their plant forms are equally pleasing. The main difference is that 'Bellefontaine' is in full bloom 5 to 7 days earlier than 'Fundy'. As well, the new growth stems of 'Bellefontaine' have a rose colour epidermal colouring whereas the stems of 'Fundy' are always green. The flower colour of 'Bellefontaine' is lighter pink than that of 'Fundy'. The stigmas of 'Bellefontaine' are dark red, those of 'Fundy' are yellow. The yellow brown blotch of both is much smaller on 'Bellefontaine'.
        The mature height and form of these cultivars are ideal for spacious landscapes but not for home foundation plantings. Properly presented they are of exceptional beauty.

Looking Back, Positive and Negative Comments
In 1983, the Kentville rhododendron programmes like similar programmes in Canada, e.g., Vineland, Ontario, the rose breeding programme at the Central Farm Ottawa, came to a halt because of economic constraints, a shortage of money and labour and because of the need to prioritize the region's most pressing horticultural needs. Breeding was terminated and the display beds relegated to very minimal maintenance.
Positive
• It was demonstrated that with very minimal cost to establish and maintain the Kentville rhododendrons became an excellent public relations asset. Widely known in Canada and the US by lectures, visitations, press and TV, it brought pleasure and knowledge to thousands of people.
• Rhododendron Sunday held first in 1967. It is a very positive annual event providing the public the opportunity to view the great varieties in plant form and quality, season of flowering, flower color, etc.
• It helped stimulate interest in rhododendrons so that today plant purchases in Nova Scotia are at an all time high.
• The great value of deciduous azaleas such as the Knaphills was demonstrated. When compared with rhododendrons the obvious thing is their superior ability to survive in challenging winter climates.
• The pleasure of having world experts such as Edmund de Rothschild and Robert Seleger visit the Station to view the plantings and take part in discussions was a great pleasure.

Dr. Don Craig and Edmund de Rothschild
Dr. Don Craig and Edmund de Rothschild.
Photo courtesy of Don Craig

Negative
• How unfortunate it is that, as of 1983, the Kentville programme ceased to function in a meaningful way.
• Rhododendron Sunday is no longer the major attraction it was.
• The very large number of new and improved rhododendrons are not on display for the public.
• A much-needed re-organization and re-vitalization of the Kentville display beds is still in limbo.

Do We Need A Breeding Programme?
Had I known in 1952 what I knew in 1975 following 23 years of extensive testing of cultivars and species I would not have become involved in a breeding programme. In 1952 I did not know with certainty the names of the cultivars in the Station's lone planting. By 1975 there were 174 cultivars and 81 species that had been or were still being tested. Many of these proved to be good performers (Agriculture Canada Pub. 1303 revised 1981).
        Breeding with commercial aspirations is anything but easy especially for the breeder with limited resources. The Kentville programme was very small. The naming of 14 selections pales in comparison with that of the late Weldon Delp who has registered 301 cultivars and the late David Leach 85. Both, like Kentville, were breeding for winter hardiness. Leach's facilities for breeding in terms of land, laboratories, manpower and money were more than adequate; Kentville is very limited in comparison (Leach, ARS Jour. Vol. 41, No. 4, 1987).
        The sheer number of introductions by Delp and Leach is mind-boggling. How does one adequately test so many? In my mind the numbers are in excess beyond reason. Adequate testing for regional adaptability was a real constraint for breeders, especially small breeders such as the late Joseph Brueckner of Mississauga, Ont. et. al.
        Reporting in his article "The Quest" (ARS Jour. V 36, No. 1) Leach states: "There followed next a group of hybrids of which too many were named perhaps because they represented a success after so many failures." Now that the market is inundated with an endless number of new cultivars, I too realize that we were in too big a rush to apply names to at least a few of our introductions. Surely from among the many cultivars from Delp, Leach and others there are new rhododendrons to more than satisfy most gardeners.
        For the moment the important thing is to have the public realize the wide range of rhododendrons available for Zones 5 and 6. There are so many plant forms to choose. Bloom dates can vary from May until mid July. The range of flower and foliage colours has increased dramatically. There is now a degree of winter hardiness in some species and cultivars to make it possible to have success even under very severe winter conditions.

More Breeding and Testing at Sunny Brook Farm
Having retired from the Research Station in 1983 I returned to the Station from time to time until 1987 in order to evaluate seedlings, especially 1,200 azaleas I produced from seed sent to the Station from Exbury in England. The seed origin was "seed from the very best Exbury plants mainly the deep red and yellows." Only 16 were selected due to the high incidence of foliar mildew. None were named.

Breeding
In 1987 my daughter (Sue Gunn) and I initiated rhododendron plantings at her 232-year-old home 9 km. north of Kentville. One acre of the 13-acre homestead is devoted to the plantings in 28 beds containing 52 azalea cultivars and 88 rhododendron cultivars plus many companion plants such as Kalmia, Pieris, Calluna and dwarf evergreens. We have also practiced my "hobby" by growing 2,816 seedlings from 73 parental combinations. Currently (2001) we are evaluating 113 selections from these crosses; 'Mist Maiden' and 'Besse Howells' were common contributors in many instances because of their winter hardiness, plant form and quality. The same can be said of 'Calsap', 'Janet Blair' and 'Scintillation'; indeed our first step was to cross 'Janet Blair' with 'Calsap' and 'Scintillation' with 'Calsap'. We grew 90 seedlings of each cross, selected the four best from each and then inter-crossed them. By back-crossing with 'Calsap' its hardiness was added, and the quality of 'Janet Blair' and 'Scintillation' were apparent in the progeny. One resembling 'Mrs Furnivall' was a highlight of spring 2002. Shammarello's 'Besse Howells' has attributes worthy of consideration - hardiness, compactness and semi dwarfness. From 18 "yak" x 'Besse Howells' seedlings we have four selections. Similarly 13 of 95 seedlings of a cross of 'Minas Rose Dawn' x 'Besse Howells' are on trial including my best red to date. SEL75-31, a 1971 cross of ('Red Head' x "yak") x ('Catalgla' x a selection of Elizabeth Group) has a nice compact truss, the colour of 'Nova Zembla', but measures only 0.9m high x 1.4m wide in 28 years. Several years ago John Weagle was impressed with selection S.94-04 from our cross of [('Bellefontaine' x R. degronianum) x 'Goldsworth's Yellow'] S.80-07 x (R. aureum x 'Prelude') BPT#80-5. The seed parent is an old KRS hybrid, very compact and a pale yellow; the pollen parent is Captain Steele's best early yellow. The hybrid is a compact mound sporting dark yellow flowers and is now on trial. As well a sibling which I feel is superior is being tested. The joy is in having them in our own garden.

Testing
During my years at the Research Station one of my main interests was the evaluation of any rhododendron or azalea cultivar or species that by definition should be suitable for Zone 5A or 5B. I have now obtained a range of new material, which was not tested at Kentville plus old standards for comparison purposes. The so-called "news" are cultivars such as Leach's 'Golden Gala', 'Normandy', 'Swansdown' and 'Cyprus'; the Mezitt hybrids 'Henry's Red', Jane Abbott Group*, 'Olga Mezitt' and 'Weston's Aglo'; Beasley's 'Top of the Mountain'*, 'Cherokee'* and 'Currahee'*; others such as 'Leann'* and Bosley 1016*.
        Many of the "new" cultivars were obtained at the American Rhododendron Society plant sales at the Annual meetings at Eugene, Oregon, Williamsburg, Virginia and Cape Cod, Mass.
        Our garden has much greater exposure to sun and wind than the Kentville planting, thus, another opportunity to rate winter damage to flower buds. This we did for five consecutive years (1993-97) using scores of 4 for full flowering; 3 good flowering; 2 for scattered flowering and 1 for all buds killed.
        Thirteen cultivars had perfect scores of 4, 24 were 3 or better which is satisfactory; the remainder had variable scores per year from 4 to 1 suggesting that in some years they would be less than satisfactory. None of the azaleas scored less than 3; most were 4 or slightly less.
        Winter temperatures for Dec., Jan., Feb., and Mar. for the 5 years were no lower than -24.9°C (-13°F) suggesting that all of the cultivars would fall within the hardiness rating of H2 yet there was significant bud damage to some cultivars in 1995 and 1996. It is worth noting that none of the deciduous azaleas were seriously damaged.
        The rhododendron cultivar 'Scintillation' is acclaimed by many to be the premier elepidote in the New England States. Its hardiness rating is H2. Its performance at my summer cottage Sunnybrook, at the Research Station and elsewhere suggested it is over rated, an indication that rating hardiness involves complex plant and climatic functions. At Sunnybrook near Chester Basin, NS, my 'Scintillation' growing within 50 meters of the Atlantic Ocean performs very well when compared to another in my home garden in the Annapolis Valley. Hardiness ratings assigned to many other rhododendrons cannot be assumed to be totally accurate. Pellet and Holt of Vermont state (Vermont News Release: 1-2, Dept. of Plant and Soil Science, Burlington) that "the selection of hardy rhododendrons should not be based solely on mid-winter cold hardiness because the rate of hardiness development is an important consideration. The hardiest evergreen rhododendron may be injured when minimum temperatures are below —15°C (5°F) in November and early December".
        Rhododendron cultivar evaluations at Sunnybrook have been very productive. We are now aware of the value of numerous new cultivars in our garden as well as a number that are not fully satisfactory. Among my favourites are 'Henry's Red', 'Golden Gala', 'Swansdown', 'Normandy', 'Melusine La Fee', Bosely 1016, 'Olga Mezitt', 'Weston's Aglo', 'Leann'*, 'Francesca' and of course my own introductions. The data on date of full bloom is useful and the minimum winter temperature information helps us to understand that low temperatures in mid—winter are not the only factors causing damage to rhododendron tissues.
        We take great pride in our garden, especially in view of having done it all by ourselves. We are the gardeners. For 50 years the beauty of rhododendrons and azaleas has surrounded me. I simply can never get enough.

* Name is not registered.

Kentville Rhododendron Cultivars
Cultivar – 'Cornwallis' (Syn. 'Acadia') (R*)
Parentage - R. fortunei, open-pollinated
Breeder - seed via Schumacker, Sandwich, Massachusetts
Introduced - 1973, Registered - 1977, D.L. Craig
Habit - large upright
Colour - dawn pink (H.C.C. 523/2)
Exposure - light shade
Hardiness - zone 5b
Bloom time - mid-season
Large deep pink flowers borne in compact trusses well above the foliage are pleasantly scented. The throat is flecked oxblood (H.C.C. 00823/3).

R. 'Acadia'
'Acadia'
Photo by John Weagle

Cultivar – 'Fundy' (Syn. 'Evangeline') (R*)
Parentage - R. fortunei x R. smirnowii
Breeder - Hancock, Mississauga, Ontario.
Introduced - 1973, Registered - 1977, D.L. Craig
Habit - very large, upright
Colour - neyron rose (H.C.C.623/3)margins, paler center
Exposure - light shade
Hardiness - zone 5b
Bloom time - mid-season
A very large rhododendron and at 40 years old, the plant is over 14 feet high. Large rose opal buds; flowers borne in large trusses above the foliage are pleasantly scented. An outstanding rhododendron that comes into its own in 8-10 years. Can exhibit yellowish foliage in excessive sun even on the Scotian coast.

Cultivar – 'Gabriel' (R*)
Parentage – 'Doctor H.C. Dresselhuys' x R. smirnowii
Breeder - George Swain
Introduced - 1973, Registered - 1977, D.L. Craig
Habit - tall
Colour - rhodamine pink (H.C.C. 027/2)
Exposure - light shade
Hardiness - zone 5a
Bloom time - mid-season
The hardiest Research Station introduction, performing well as far north as Fredericton, New Brunswick.

Cultivar – 'Minas Grand Pré' (Syn. 'Grand Pré') (R*)
Parentage - R. catawbiense compact form x R. williamsianum
Breeder - George Swain
Introduced - 1973, Registered - 1996, D.L. Craig
Habit - semi-dwarf, compact
Colour - pale purplish pink (RHS 62D)
Exposure - light shade
Hardiness - zone 5b
Bloom time - mid-season
An outstanding semi-dwarf plant with small attractive roundish leaves which flush a copper colour similar to that of its pollen parent. Loose attractive clusters of attractive bell-shaped pink flowers. A must for every garden in hardiness zone 5b or milder. It seems very happy in the garden of Peter Cox in Glencarse, Scotland.

R. 'Minas Grand Pré'
'Minas Grand Pré'
Photo by Sterling Levy

Cultivar – 'Bellefontaine' (R*)
Parentage - R. fortunei x R. smirnowii
Breeder - R. Pike, Lubec, Maine
Introduced - 1975, Registered - 1977, D.L. Craig
Habit - very large upright
Colour - rose opal (H.C.C.022) in bud, opening neyron rose (H.C.C. 623/3 in throat, to 623/1 margins)
Exposure - light shade
Hardiness - zone 5b
Bloom time - mid-season
Judged by many as the Research Station's outstanding introduction. A seedling from the same cross that produced 'Fundy'. Very tall (14+ feet) in 40 years. Pleasantly scented neyron rose flowers are borne in large trusses above the foliage. Very good plant form but only comes into its own after 8 to 10 years.

R. 'Bellefontaine'
'Bellefontaine'
Photo by John Weagle

Cultivar – 'Minas Peace' (R*)
Parentage - [(R. catawbiense 'Catalgla' x R. degronianum) x R. yakushimanum (now R. degronianum ssp. yakushimanum)]
Breeder - D.L. Craig
Introduced - 1982, Registered - 1998, D.L. Craig
Habit - medium tall
Colour - white suffused pink
Exposure - light shade
Hardiness - zone 5b
Bloom time - mid-season
This is one of my favourite rhododendrons. The excellent foliage has a thick covering of attractive grey-orange indumentum on the leaf undersides. This habit is semi-compact. The flower buds, strong purplish pink (RHS 55B), open to pale purplish pink (RHS 56A), striped a strong purplish pink (RHS 55B) on the reverse of each petal. Flower trusses compact and above the foliage. A plant for all year round.

R. 'Minas Peace'
'Minas Peace'
Photo by Don Craig

Cultivar – 'Minas Maid' (R*)
Parentage – 'Nova Zembla' x R. yakushimanum (now R. degronianum ssp. yakushimanum)
Breeder - George Swain
Introduced - 1979, Registered - 1979, D.L. Craig
Habit - medium tall, compact
Colour - moderate purplish pink (RHS 62B)
Exposure - light shade
Hardiness - zone 5b
Bloom time - early mid-season
This most reliable rhododendron possesses a very good level of winter hardiness. Compact growth habit. Basic colour is purplish pink. The ball-shaped truss is held above the foliage. Foliage quality is very good. Very floriferous.

R. 'Minas Maid'
'Minas Maid'
Photo by John Weagle

Cultivar – 'Minas Snow' (R*)
Parentage – 'Cunningham's White' x R. yakushimanum (now R. degronianum ssp. yakushimanum)
Breeder - George Swain
Introduced - 1981, Registered - 1998, D.L. Craig
Habit - medium tall
Colour - white
Exposure - full light
Hardiness - zone 5b (plant), 6a (flower buds)
Bloom time - mid-season
Compact growth habit and dark green foliage. Underside lightly covered with a tan coloured indumentum. Flower quality is outstanding. Flower and bud pure white. Flower trusses held well above the foliage. 'Minas Snow' is highly regarded as an excellent white on the West Coast and eastern seaboard of the USA. Inexplicably it sometimes exhibits bud damage in early December on the Scotian coast.

R. 'Minas Snow'
'Minas Snow'
Photo by Don Craig

Cultivar – 'Minas Rose Dawn' (R*)
Parentage - ('Nova Zembla' x R. yakushimanum [now R. degronianum ssp. yakushimanum]) x (R. catawbiense var. album 'Glass' x 'Elizabeth')
Breeder - D.L. Craig
Introduced - Ag. Research Station, 1982, Registered - 1997, A.R. Brooks
Habit - medium height, wider than tall.
Colour - red-purple
Exposure - light shade
Hardiness - zone 5a
Bloom time - mid-season
Flower trusses compact and above the foliage. Buds strong purplish red (RHS 67A), very attractive, open funnel shape. The petal edges are wavy and vivid purplish red (RHS 67B); main body moderate to pale purplish pink (RHS 65A-D); extensive moderate red (RHS 180 A-B) spotting on inside of dorsal petal. Very floriferous.

Cultivar – 'George Swain' (R*)
Parentage – 'Goldsworth Yellow' x (R. catawbiense 'Catalgla' x Theresa Group)
Breeder - D.L. Craig
Introduced - 1988, Registered - 1998, D.L. Craig
Habit - medium tall, compact
Colour - pale yellow (RHS 158B)
Exposure - light shade
Hardiness - zone 5b
Bloom time - early
Early flowering, pale yellow (RHS 158B), of value because of its earliness and good semi-compact habit. Globular dome-shaped truss held well above the foliage.

Cultivar – 'Mary Craig'**
Parentage – 'Goldsworth Yellow' x R. degronianum
Breeder - George Swain
Introduced - 1981
Habit - semi-dwarf, compact
Colour - pink, buds dark pink
Exposure - light shade
Hardiness - zone 5b
Bloom time - early
A good semi-dwarf compact plant. Flower buds dark pink opening light pink. Flower trusses held above the foliage.

Cultivar – 'Sue Gunn' (R*)
Parentage - ('Nova Zembla' x R. yakushimanum [now R. degronianum ssp. yakushimanum]) x (R. catawbiense 'Catalgla' x 'Elizabeth')
Breeder - D.L. Craig
Introduced - 1992, Registered - 1992, D.L. Craig
Habit - medium tall, compact
Colour - vivid purplish red (RHS 57B) with black spotting on dorsal lobe
Exposure - light-medium shade
Hardiness - zone 5a
Bloom time - mid-season
Spectacular in terms of its bright showy colour which is purplish red. Wavy flower margins. Black spotting on the dorsal lobe. Very floriferous with a dense growth habit; it puts on a good show even from a distance.

R. 'Sue Gunn'
'Sue Gunn'
Photo by Don Craig

Cultivar – 'Minas Princess' (R*)
Parentage - open-pollinated Ghent azalea hybrid
Selected by D.L. Craig from seed via Schumacher, Sandwich, Massachusetts
Introduced - 1982, Registered - 1998, D.L. Craig
Habit - upright, tall
Colour - light purplish pink (RHS 55C)
Exposure - full sun to light shade
Hardiness - zone 5a
Bloom time - mid-season
This is an excellent azalea. The flowers are very attractive, the scent very pleasant.

R. 'Minas Princess'
'Minas Princess'
Photo by Sterling Levy

Cultivar 'Minas Flame' (R*)
Parentage – 'Gibraltar' x 'Balzac'
Breeder - George Swain
Selected by - D.L. Craig
Introduced - 1982, Registered - 1998, D.L. Craig
Habit - upright, tall
Colour - vivid reddish orange (RHS 33A)
Exposure - full sun - light shade
Hardiness - zone 5b
Bloom time - mid-season
This hybrid has the appearance of most Knap Hill azalea cultivars and is a strong growing plant. It has a good level of mildew resistance. Its orange-red flowers are attractive.

* Royal Horticultural Society Certificate of International Registration.

** Name is not registered.

N.B. Many of these hybrids may require more sun on the Scotia coast where fog is prevalent.

N.B. In 1980 I selected and named a seedling azalea 'Minas Gold' because it was mildew resistant at the time and for a period afterwards. It later, however, proved that this resistance was not present and so I discarded it. Perhaps 'Minas Gold' was an escape or another strain of mildew caught up with it. 'Goldflake', for example, is a vastly superior cultivar.

N.B. Various Kentville hybrids can be purchased at Bayport Plant Farm, Bayport, Lunenburg, NS. 'Minas Grand Pré' (aka 'Grand Pré') is available in small sizes at Blomidon Nurseries, Greenwich, NS; Lakeland Plant World, Dartmouth, NS, Gerryls Nursery, Centreville, NS and Murray's Garden Centre, Portugal Cove, NF.

Dr. Craig is a member of the RSC Atlantic Chapter.


Volume 59, Number 1
Winter 2005

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