The Hardy Ghent Azaleas
Albert De Raedt
Asper (Gavere) Belgium
Reprinted with permission from Rhododendrons with Camellias and Magnolias 1998, published by the Rhododendron, Camellia and Magnolia Group, Royal Horticultural Society.

It would not be modern botanical practice to describe under one collective name a group of plants whose origin is so varied as the Hardy Ghent azaleas. We speak about mollis, viscosum or occidentale hybrids where, in each case, one of these species is a parent. The Hardy Ghents, however, are the product of crossings between at least five distinct species - Rhododendron calendulaceum , R. flammeum ( Azalea speciosa ), R. peryclymenoides ( A. nudiflora ), R. prinophyllum ( A. rosea ), R. viscosum and R. luteum ( A. pontica ). Subsequently R. molle ( A. sinensis ) and in some cases R. occidentale were also successfully used. Some examples today of the first group would be 'Daviesii', 'Unique', and 'Nancy Waterer', and of the second, 'Magnificum' and 'Magnificum Albicans'. It should be noted, incidentally, that there is also an occidentale hybrid named 'Magnificum'.

Contrary to what the group name, Hardy Ghent, might indicate, Ghent in Belgium was not the only place where these azaleas were hybridized, but it was, very probably, the first. The original hybridization seems to have been undertaken at the beginning of the 19th century, by an amateur grower, P. Mortier (1768-1847), who was a baker by profession. His hybrids were named Azalea mortieriana , A. mortierii , or by other variants of his name. At a later date, he crossed his hybrids with the yellow flowered hardy and sweet scented R. luteum ( A. pontica ). It was the resulting plants that became known as "Harde Ghentse azaleas," "Azalées rustiques de Gand," or "Hardy Ghents" or in the Netherlands and Germany, as "Pontica hybrids."

In 1834 Mortier sold his last hybrids to the nurseryman Louis Verschaffelt. At about the same period a Mr. Gowen on behalf of the Earl of Carnarvon at Highclere, in the county of Berkshire, England, must have made crossings with the Mortier hybrids. He too used Rhododendron molle and R. viscosum . Less well known are the crosses made by a Herr Rinz in Germany. In about 1833 he seems to have succeeded in crossing Mortier's hybrids and A. pontica 'Flora Albo Pleno'. I doubt if any present day connoisseur has knowledge of this azalea, but that is how it was described in Gartenflora of 1854. That description states that from these crossings twelve (all doubles) were selected, but only two were mentioned by name. These were 'Grafvon Meran' and 'Chromatella', as indeed they are still known to this day. In 1855 Ambroise Verschaffelt, who in 1850 had succeeded to the business of his father Alexander, the brother of the Louis Verschaffelt already mentioned, published a list of eleven double flowered Hardy Ghents, stating that they came from Germany. It was only later that the name of Rinz was mentioned.

In France also, there were, quite early on, some growers who contributed to the abundance of new varieties that flooded the market. It is a pity that, as yet, we have been unable to discover adequate documentation. However, it is possible to quote some of the names, such as Sénéclause with 'Coccineum Speciosum' and 'Gloria Mundi', Quihou with 'Fritz Quihou' (a fine red); Croux and Moser.

In 1846 a first list of twelve hybrids ascribed to M.L. Verschaffelt was published, in Belgium, in the Annales de la Societé Royale d'Agriculture et de Botanique de Gand 'where they were still referred to as A. mortieriana ( mortierii ) var. hybridae . The following year a further eight were added. In his pricelist of 1849 Louis Van Houtte writes that he is offering twenty-five new varieties, styled the Louis Verschaffelt collection. Table C compares the Van Houtte list with the two Annales lists of 1846 and '47. The cultivars printed bold in the Van Houtte list have survived in collections to the present day. If one compares the two lists one finds that some cultivars had been renamed. There exist also the lithos of 1846 and 1847, exactly as originally published in the Annales .

In 1855 the Illustration Horticole published, also in colour, sixteen new Hardy Ghents together with ten double-flowered hybrids. These are described in Table A, and again those cultivars known to be still in cultivation are shown in bold.

In 1873 the Flore des Serres et des Jardins de l'Europe, tome XIX , published by Louis Van Houtte, contained a description of twelve new Hardy Ghents, among them six (including a colour reproduction) he says he obtained from the widow of a Louis Hellebuyck. It said that this grower, by tenacious crossing and selection from thousands of seedlings, that had A. pontica as the mother plant, and as male parent one of several species from the eastern United States ( A. calendulaceae , A. nudiflora , A. viscosa , and A. bicolour ), had produced the following six azaleas. Again those cultivars known to be still in cultivation are shown in bold.

'Louis Hellebuyck' ; 'Mad. Alex Hardy'; 'Mina Van Houtte' , Louis A. Van Houtte' ; 'Francois de Taye'; 'Bijou de Gentebruggen' .

In pricelist no. 174 of 1877, twelve "nouveautés" were mentioned, unclassified by under the name "Van Houtte"- 'Francois De Taye'; 'Bijou de Ghentbrugge' ; 'Mina van Houtte' ; Louis Aime van Houtte' ; 'Mad. Alex Hardy'; Rose de Flandre' ; Domenico Scassi' ; 'Dr. Auguste Cambier'; 'Fidele Mechelynck'; 'Sang de Gentebruggen' .

Only in the 1870s did it become customary to present the different cultivars with a colour description, descriptions with commercial intentions that were not always uniform and certainly not always accurate. Colour numbers as we use them now were unknown at that time. From the various pricelists, discovered in different libraries by a fellow member of the Belgian Dendrological Society, Leon Declerq, it has been possible to gather together a list of almost 1,000 different names, although certainly including a number of synonyms. Mostly names are given without a colour description, but these are known for 600 cultivars.

The next phase of the investigation, undertaken originally by Leon Declerq, and subsequently also by J. Delvaux and myself, consisted of endeavouring to trace which cultivars were still available and where they were located. So far we have had success in Belgium at the Arboretum in Kalmthout, at the Castle in Beervelde, and, of course in Leon Declerq's own garden; in Germany in the Rhododendronpark at Bremem and at the show garden of the Horticultural Institute at Bad Zwischenahn; in England at the beautiful collections at the RHS Garden, Wisley, the Sir Harold Hillier Arboretum, the National Trust Garden at Sheffield Park, Sussex, and the Royal Botanic Gardens, Kew. Unfortunately most of the plants in these collections are not labeled. Our information about collections in France and the Netherlands is very scarce. The only well known specialized commercial nursery, through the assistance of Leon Declerq, is the nursery De Keyser-Matthijs, which is situated at Lochristi, near Ghent. In total we have, so far, recorded on computer 135 cultivars held in twenty public or private gardens, in Belgium, Germany, the United Kingdom, and the USA.

Closely related to the Hardy Ghents are the Rustica azaleas. The situation of this group of deciduous azaleas is totally different, for the following reasons. We know exactly when they were brought onto the market, that is by a single nursery in the period 1888-1900; they are all double flowered and sweet scented. And yet here also we find many unanswered questions. Charles Vuylsteke of Lochristi showed his novelties (probably eighteen) for the first time in Ghent in 1888. However we have been unable to trace his pricelist. He called them "Azalea Rustica Flore Pleno," and also "Azalea mollis," "Hybrides a fleurs doubles."

The fact that Vuylsteke uses the description A. mollis hybride (i.e., R. japonicum ) suggests that there is another species or cultivar involved, but which one? Here is a much larger problem. Vuylsteke probably did not know himself which was the other parent, as he had not carried out the crossing and selection of the eighteen himself. This had been done by a Louis De Smet, but he had since died, and exactly like Mortier sixty years earlier, he had told no one which crossings he had made. It is quite probably that he had made crossings unsystematically with several species. Some think that he may have crossed R. japonicum with R. occidental or with an occidentalis hybrid. But this would not produce double flowered specimens. It is almost certain that a double Hardy Ghent must have been involved as the mother plant (because they seldom or never have stamens).

There are also different views about the assortment. In Vuylsteke's offer as printed of 1913, there were twenty-six different cultivars, numbered 400 to 426. The numbers 400 to 417 are the same as the original offer of 1888. The next five are believed to have been added later on. 'Teniers', 'Quentin Metsys', 'Corneille', 'Racine', and 'Fenelon' are all still in our gardens. No. 424 'Dyogine' was offered only once by Vuylsteke, and was never offered by any other nurseryman. In Rhododendrons and Azaleas by H. Grootendorst (published 1954), it is stated that only the first eighteen can be considered as Rusticas and that the remainder belong to the double Hardy Ghents, because they produce too many leaves and show too vigorous a growth. However neither Ch. Vuylsteke nor any of his colleagues made such a distinction.

The only cultivars on the 1900 list it has not been possible to identify in current cultivation, up to the present moment, are Nos. 418 and 419, 'Rubens' and 'Van Dyck'. The mistake should not be made of confusing these two Rusticas with the Hardy Ghents of the same names on the list published in 1846 (Table C). Finally, Table B illustrates the complete list as printed in 1913.

Albert De Raedt lives near Ghent in Belgium and is a member of the Belgium Dendrological Society. He is preparing a book on Hardy Ghent azaleas for publication.