Rhododendron Growing in New Zealand; Its Past, Present, and Future
J. S. Yeates,
Palmerston North, New Zealand
(From Presentation Given at 1972 Annual Meeting, San Francisco)
FIG. 76. Sketch map of New Zealand, with main
places marked for references in text.
First of all, a brief description of the geography and climate of New Zealand is necessary. The country consists of two main islands, the North and South Islands respectively, with two-thirds of the population in the North Island. We extend over about one thousand miles roughly North to South, the southernmost part being at about the latitude of Portland, Oregon, the most northern corresponding almost to that of Los Angeles, California. Naturally we are "upside down" from your point of view, the northern part having the climatic equivalent of Los Angeles and the southern part resembling Portland. However the narrow, insular nature of the land results in a rather more moderate range of temperature than in your case. The prevailing winds are from the west and the presence of a backbone of mountain ranges running down the middle of most of the two islands, results in the western side being in general the wetter. Another point about the mountain ranges is that they provide areas of land near the coast, yet at considerable elevation and with a higher rainfall. In the North Island this permits of successful rhododendron growing which is not so easy on the warmer and drier atmosphere of the coastal lowlands. In many parts of the South Island, the cooler climate allows rhododendrons to grow very well at low altitudes. These remarks are, of course, true only in a general way and exceptions are often found, ether in small pockets of natural microclimates, or where skillful gardening has overcome the difficulties. North of about latitude 39, coastal areas are virtually frost-free and from latitude 37 northwards again the climate is so mild that growing normal rhododendrons is hardly practicable. It is in these mild and coastal regions that subtropical types and the Malaysian species may be found suitable, provided humidity can be maintained. North of Auckland, for instance the rainfall varies from about 60 to 100 inches per annum, with oppressive summer humidity and temperatures rarely reaching 85° F. These conditions could make the Malaysian rhododendrons well worth trying out of doors. Rain falls on about 170 days in the year in most of the districts where the rhododendrons are grown. Generally the driest months are in late summer - January, February and March.
It must be remembered that our flowering seasons, like our latitudes, are reversed as compared with those in the northern hemisphere. Flowering starts in June-July, with 'Winter Cheer' followed by 'Cornubia' and various forms of R. arboreum (especially 'Mrs. Henry Shilson'). The height of the season is in late October most years, with the Ilam azaleas generally making their best display in early November.
FIG. 77. R. 'Sir Robert Peel' as a street
tree in downtown Rotorua, N. Z.
Planted 1923-'24, photographed 1972.
FIG. 78. R. 'Sir Robert Peel' as street trees in Rotorua,
New Zealand. Planted 1923-24; photographed 1972.
Photos courtesy Dr. Yeates
To the best of my knowledge, no historical records are available as to the earliest importation of rhododendrons to New Zealand. One thing is certain; the early settlers were from England and they brought with them not only a love of gardening, but also seeds and plants which they fancied. Probably some of the earliest rhododendrons were imported in this way and later propagated by nurserymen. The early hybrids such as 'Sir Robert Peel', 'Elegans', and 'Sappho' seem to have been introduced very early, to judge from the number of old trees of these clones which have been planted in many parts of the country.
The collecting of seed from Asian species by Sir Joseph Hooker and later by Robert Fortune in the 1850's was no doubt followed not long after by seeds and plants of these species reaching New Zealand. Certainly R. thomsoni and R. griffithianum were used to produce near Dunedin in 1890 a hybrid known well in our country as 'Marquis of Lothian'. The raiser was a Scottish gardener, Mr. William Martin. About 1860 Sir Cracroft Wilson, a magistrate from Manipur in India, settled near Christchurch, New Zealand. He brought with him seeds of R. arboreum , and about 1914 Edgar Stead secured some of these large old plants and planted them in his newly acquired 15-acre property 'Ilam', Christchurch. One of these was particularly good, having a fine red colour and a good head of up to 24 florets. Edgar Stead used this plant extensively in his breeding in later years.
Another very early introduction was of a plant which is of uncertain origin but called 'Lady Galway'. The original plant was imported by a Mr. Mason ('Quaker' Mason) to Wellington, reputedly from the Orient in a Wardian case in the days of sailing ships. It is a plant of Series and Sub-series Maddenii , bearing heads of usually three flowers, rich fleshy-red in the bud and opening to pale pink and well scented. Mr. Mason imported plants from many parts of the world and his garden was well known. The late Peter Black secured cuttings of 'Lady Galway' when the garden was subdivided for housing after the first World War. Mr. Mason's great grand-son tells me that the rhododendron trees were cut for firewood of which they produced 10 cords. One cord of firewood is a stack 8 feet by 4 feet by 4 feet. Such is the fate of suburban rhododendron plantings! Mr. Mason imported his plants mostly about 1850. 'Lady Galway' has never been seen to produce seed, so maybe it is a hybrid.
Although the hardy hybrids and a few Himalayan species ( R. griffithianum , R. arboreum , R. thomsonii , R. barbatum , R. grande etc.) were grown before 1914, the species were in very small number. From that time onwards, partly from the interest created by Millais' great book, and partly because of the expeditions such as those of E. H. Wilson, George Forrest, Kingdon-Ward, and others, interest began to grow and several enthusiasts commenced importing plants, mainly from English nurseries. The main (private) importers were James Speden of Gore, David Scannell of Hastings, Percy Thomson of Stratford, David Tannock of Dunedin Botanic Gardens and especially Edgar Stead of Christchurch. These were the men who showed the value of the newer species and hybrids, and the nursery trade in rhododendrons developed, mainly on the basis of hardy hybrids imported in bulk from Holland.
This might be termed the end of the first phase of our Rhododendron growing and we should pause to consider what lessons can be learned from the early plantings. In general they have suffered the fate of Mason's garden - destroyed for housing purposes - or else they have degenerated when the original collector could no longer care for them. They have become overcrowded and succeeding generations have lacked either the interest or the means to maintain them. It is true that they served to stimulate interest in the genus and provided propagation material for nurserymen and others.
The main exceptions have been the plantings at the Dunedin Botanic Gardens and Edgar Stead's plantings at "Ilam" - now owned by the University of Canterbury and likely to be maintained to some extent, though in great need of thinning. The moral is that, as has happened with many of the great rhododendrons in Britain, large plantings cannot be maintained in good order over the generations except under some form of public ownership.
What might be called the present stage of rhododendron growing in New Zealand might well be considered to have been initiated by the work of Edgar Stead at "Ilam", the first President of our Association.
From the first World War he devoted his time to rhododendron growing and to ornithology. He bought the 15-acre property "Ilam" on the outskirts of Christchurch and having inherited a comfortable living, he was able to devote his whole time to his hobbies. He was a man of considerable ability (he graduated in engineering), with keen powers of observation and a most critical mind. He belonged to the English Rhododendron Society and visited England about every two or three years. He was an expert with the shot-gun, once winning the annual competition at Monte Carlo. With these interests and qualities he knew the owners of many of the great Rhododendron gardens in Britain and obtained large numbers of plants from them. In return he sent large consignments of New Zealand plants to his friends. Many of his plants came from Exbury and the initial breeding stock for his 'Ilam' azaleas came from Knaphill, though Lionel de Rothschild allowed him to make crosses at Exbury and later sent him the seed.
He raised thousands of hybrid plants, selected the best for his own garden and sold the rest to most willing purchasers. His hybridizing has already been reported in the 1947 Rhododendron Year Books of both the R.H.S. and A. R. S. Apart from his 'Ilam' azaleas, probably those of his hybrids which have best stood the test of time are 'llam Orange', several of the clones of the 'Scarlet King' grex; his R. sinonuttallii x R. lindleyi ; and a beautiful cream Loderi.
To set the record straight it should be pointed out that 'Scarlet King' really includes two grexes. (See Stead R.H.S. Y.B. 1947 pp. 46-47.) One grex involved R. barbatum , the other did not. One clone in particular was pointed out to me by Mr. Stead as the R. barbatum cross. This is the one known as 'Orchard'. These crosses include some really brilliant reds, which are hardy wherever I have seen them grown in New Zealand, but at Tacoma, Wash., in the garden of Dr. Charles Berry, they barely survived.
It was the enthusiasm created by Edgar Stead's rhododendrons that was mainly responsible for the founding of the New Zealand Rhododendron Association in 1944. The aims were not only to serve as a common meeting ground for enthusiasts, but to encourage the growing of rhododendrons. Each member was to receive two plants annually, at cost price, and we set up a small organization to propagate these - first from Edgar Stead's hybrids, then also from seed of species from Edinburgh Royal Botanic Garden, from the R.H.S., and from Kingdon-Ward's expeditions, to which we subscribed. We also propagated good forms of plants from numbers of gardens, imported plants and later scions of the later hybrids from gardens like Exbury and Bodnant. All these plants were propagated and distributed to members. Exbury azaleas in their award forms were imported and crosses were made between these and the best 'Ilam' azaleas, as well as between Ilam clones. These have been distributed to members in large numbers. Crosses between evergreen rhododendrons have also been distributed as unflowered seedlings. We now subscribe to the Rhododendron Species Foundation and to Rhododendron Venture - the aim being to secur propagating material of new forms for distribution. It must be remembered that in our climate we can grow readily forms which could never be obtained from Britain because they are not hardy out-of-doors there. The lovely old hybrid 'Fragrantissimum', for instance, is easy to grow and very common with us; R. nuttallii , R. lindleyi and the beautiful hybrids between these two grow and flower freely over most of the country. For such reasons we try to secure the more tender forms direct from their native haunts, rather than restrict ourselves to types which have had to prove their hardiness in Britain and similar climates.
We are growing some of the Malaysian species, thanks to Michael Black and to Australian growers. The rich colours and scent of some species are most attractive. They will probably need to be grown as indoor plants except in some of our milder climates, such as the northern half of the North Island. We have of course been growing stock bushes of our imported plants to secure propagation material. These have in the past mainly been grown at Massey University at 100 feet altitude in silty soil apt to become rather damp in winter. Phytophthora has caused severe root trouble, so we commenced growing some 30 miles away at Kimbolton in a very free draining soil at 1600 feet altitude. Because growth is so good there, we have now bought 7 acres of land and in May 1971 shifted about 500 plants (some 6 feet high) on to this area. We have built a club house, a pond, and plan to have a trial ground which will be a source of propagating stock and a place of beauty which can be maintained in perpetuity, by reason of our Association's permanent existence.
One important rhododendron development should have been mentioned earlier. One of our members, the late W. D. Cook, bought several hundred acres of mountain land in 1954 and offered it to the Association as a "home". At that time we could not finance the venture, so a group of our members set up an organization, the Pukeiti Rhododendron Trust. This has a large membership and has built a fine Lodge and planted hundreds of rhododendrons and azaleas. There is close cooperation between our Association and Pukeiti, and many growers are members of both organizations.
So much for the present. What can we foresee as to rhododendron growing in New Zealand?
There will always be the large rhododendron garden. under woodland conditions of shade and shelter. Those in private ownership will mainly be on the larger farms where there is ample room for large plants and their shelter trees to grow. Heavy death duties and lean financial farm returns, or lack of interest from a new generation, makes the future of these large plantings precarious, but we can only hope for the best. In town and suburban areas the garden large enough to grow tree-sized rhododendrons is always precarious. As the town extends, values rise and city rates can become so high that sale for subdivision become necessary. New large gardens planted still further from the town center are likely to suffer the same fate after one or two generations; so we are likely to have this type of garden for a long time, due for the bulldozer after a generation or two.
In the newly subdivided areas, some large rhododendrons may survive, but lack of room for shade and shelter will force the growing of the smaller, more compact types which need less protection from exposure. The deciduous azaleas may well become more popular under these conditions. Not only are they hardier to exposure and to soil conditions, but they make a brilliant display, many have good autumn foliage colour and they recover well when too large, even if cut right back to ground level. Cut some back each year and there will always be a proportion of flowering-size plants. Selection from oft-discarded small plants might even produce a race of dwarf deciduous azaleas.
Dwarf evergreen rhododendrons, though lacking the majesty of a Loderi, will be certain to grow in popularity in these smaller gardens. Plants like 'Creeping Jenny' and 'Elizabth Hobbie' in the reds; R. moupinense , R. leucaspis , and others should be considered. R. anthopogon is one which can be planted for scent. The smaller-growing evergreen azaleas have never been really popular with rhododendron growers in this country, but they probably will have their place in small gardens.
Many of the dwarfs can well be grown in large pots, plunged outside in a suitable place in summer and brought indoors just before flowering. Some of the Malaysian species, grown under protected conditions out of doors and pruned to less straggly growth, could perhaps be used in this way also.
Even rhododendrons which will ultimately become too large for container grown house plants should not be overlooked. Compact types such as R. yakushimanum and some of its hybrids make delightful, small, compact and colourful pot plants.
The kurume azaleas, of course have long been used in this way and no doubt the practice will extend.
There is still the question of where the larger rhododendrons will be grown. It appears that more and more the tendency will be for them to be grown in the larger plantings, generally supported by public or private organizations with the necessary continuity to ensure proper maintenance. Public parks and botanical gardens, private plantings like your Portland Trial Grounds, our Pukeiti, or our Kimbolton plantings, offer the best chances.
One city in New Zealand (Wellington), by no means ideal rhododendron country, last year planted 500 flowering-size Ilam azaleas and the results were so good that the aim is to plant another 500 or more as soon as possible. Rotorua, a small city in the center of our thermal springs area is planting large numbers of evergreen rhododendrons in parks and on street sides. In one year they planted 4,000, half of which were in the streets. Old hardy varieties planted there some 47 years ago as street trees are now up to 30 feet high and wide enough to park cars under them for shade. The newer plantings in streets include varieties such as 'Cornubia' and 'Ivory's Scarlet'. We hope to supply them with propagating material of newer tall growing sorts suitable for street planting.
Finally one important problem for the future is permanent naming of plants now, in our large collections. Those of you who read the R.H.S. Rhododendron Year Book, will have read of the great trouble and labour involved in tracing the identity of rare plants at Nymans even in a planting where labeling had been carefully done. We certainly need a conspicuous name peg for the casual observer; the problem is that in maybe 25 or 50 years pegs can have been misplaced or neglected. Perhaps a name embossed in thin non-corroding metal, fastened to the tree by a very loose non corroding wire is the best answer. In this, as in much else I have said, I am putting out feelers which I hope will provoke some good answers to the problems that concern me greatly.
In the genus Rhododendron we have a truly wonderful group of plants, offering an almost infinite variety in size, habit, leaf, flower colour, scent, and in their varied requirements for successful culture. Above all we grow them because they are a great joy to behold and to grow, and any effort we can make to that end, is truly a labour of love that benefits the whole community.