American Rose Annual 32:173-192 (1947)
Classification and Breeding of Polyantha Roses
By DR. WALTER E. LAMMERTS
Rancho del Descanso, La Canada, California

THE polyantha roses are becoming increasingly important not only in the Eastern States where they have long held an important place in the landscaping of the larger homes, estates and parks, but also here in California where they have hitherto been used only sparingly. This increased popularity is largely due to the introduction in recent years of varieties combining the everblooming cluster habit of the older types with greatly improved flower color and form. Continued development of this class of roses by plant breeders depends on a thorough understanding of the history, classification and varietal diversity of already existing polyanthas so that future breeding efforts may take full advantage of the many accomplishments already achieved. It is the purpose of this article to point out some of the problems involved in classifying this highly diverse group of rose varieties, discuss the characteristics of certain important sub-groups, and indicate what seem to be worthwhile leads for rose breeders to follow in developing the ideal polyanthas of the future.

The most complete descriptive list of polyantha varieties is that found in Modern Roses II where they are arranged alphabetically along with the other varieties and classified into two groups, i.e., polyanthas and hybrid polyanthas. Presumably the polyanthas are those varieties having varying combinations of genetic factors from only two species, Rosa multiflora and Rosa chinensis, and the hybrid polyanthas are varieties resulting from crossing polyanthas with varieties in other classes or with other species of roses. Unfortunately, such clear-cut distinction is evidently very difficult, as will be made clear later in this paper. The original members of this group were distinct enough to be readily classified, as they all combined the small-flowered cluster habit of R. multiflora with the dwarf bush and continuous blooming habit of R. chinensis. Thus, the Crimson Rambler, imported from Japan in 1893 as the Engineers Rose, was a vigorous climber having irregular double bright crimson flowers which faded badly to blue. This variety was crossed by Levavasseur in 1903 to Gloire des Polyanthas to give Mme. Norbert Levavasseur, a bushy dwarf plant of continuous blooming habit but still retaining the crimson flower which "blues badly." Evidently Gloire des Polyanthas transmitted the dwarf everblooming habit from its R. chinensis ancestry. By crossing Mme. Norbert Levavasseur with an unrecorded variety, Levavasseur obtained and introduced in 1909 the famous Orléans Rose, typical of many true polyanthas. This rose had vivid rosy crimson flowers with a white center, glossy leaves, a bushy habit and free intermittent bloom all season. A truly remarkable array of sports have come from the Orléans Rose, and some of these have in turn sported again. The list of these sports, arranged chronologically, is as follows:

ORLÉANS ROSE (1909) — vivid rosy crimson, white center.
Miss Edith Cavell (1917) — scarlet crimson, overlaid velvety crimson (never blues). Should be very valuable in breeding.
    1. Ideal (1921) — dark velvety crimson.
        a Orange Perfection (1927) — orange red.
        b Julia Ann Bostick (1935) — apple blossom pink, white at base; single flower.
    2. Kersbergen (1927) bright currant-red.
    3. Orange Marvel (1928) salmon orange.
Coral Cluster (1920) — coral pink
    1. Pride of Hurst (1926) — coral pink, small, very double.
    2. Little Dorritt (1930) — coral salmon.
Juliana Rose (1920) — pale salmon.
Koster's Orléans (1920) — brilliant scarlet red.
Frau Elisabeth Munch (1921) — full scarlet cherry red.
Crimson Orléans (1922) — dark red.
Girlie (1923) — bright scarlet crimson.
Double Orléans (1924) — rosy crimson, white center, more double than Orléans rose.
Locarno (1926) — large orange red.
    1. Scarlet Button (1932) — brilliant scarlet.
Magnifique (1928) — clear pink.
Orange Queen (1923) — salmon orange.
Teschendorff Jubilaumsrose (1928) — brilliant rosy crimson darker than Orléans Rose.
Orléans Improved (1931) — vivid rose pink.
Gloire du Midi (1932) — brilliant orange scarlet.
Cameo (1932) — salmon pink.

From the genetic point of view the interesting features of this list of 24 sports of the Orléans Rose are (1) the variation in color, (2) the variation in size of flower and degree of doubleness, Pride of Hurst being small and very double, and Julia Ann Bostick single flowered; and (3) the re-occurrence of the same color sports several different times. Thus there are six sports described as having brilliant scarlet or currant-red flowers, three with coral pink or salmon flowers, two with salmon orange flowers, and two with orange red flowers. Furthermore, these colors are clearly recessive to the vivid rosy crimson of the Orléans Rose, since in no case do we find varieties having these colors sporting back to crimson again. This is in line with the results of breeding data briefly presented previously (Lammerts 1945). The dark velvety crimson of Ideal is similarly recessive to the scarlet crimson of Miss Edith Cavell. The recorded statement that Miss Edith Cavell never blues is most interesting, as it would seem to indicate the reappearance of the non-bluing quality found in many R. chinensis varieties, and the recessive inheritance of this valuable trait. Varieties having this characteristic should be most valuable in breeding work. It would be decidedly worth while to gather all 24 of these sports in one collection to determine if all are really distinct, or if the same sport has occurred two or more times, resulting in identical varieties.

Other less complicated families of sports in the true polyantha class are (1) the double crimson Superba and its twin family of sports, Golden Salmon which sported to Sparkler and Ceská Pohádka, and Gloria Mundi which sported to Luminous, California Gold, Canberra, Coral Cup and Baby Gloria; (2) Phyllis which sported to Jessie, Orange King and Osmunda, Jessie in turn sporting to Marytje Cazant, Marytje Cazant then sporting to Perfection, and Orange King sporting to Mariposa, Salmon Beauty, Lindbergh, Fireglow and Frau Rudolph Schmidt; and (3) Tausendschön which sported to Echo, which in turn sported to Brilliant Echo, Direktor Struve, Eva Teschendorff and Greta Kluis, the latter sporting to Präsident Hindenberg. The recessive behavior of white is indicated by the occurrence of the two white sports, Direktor Struve and Eva Teschendorff from the dark pink Echo.

A list of true polyanthas is given in Table I. As far as the evidence given in Modern Roses II indicates, these have been derived only from R. multiflora X R. chinensis sources. Since the data on some is very meager their true nature could only be ascertained by growing them together in a collection, studying carefully their expressed characteristics, and probably also making a genetic analysis of any varieties which seem distinct enough from obviously true polyanthas such as the Orléans Rose to be suspected as having factors from species other than R. multiflora or R. chinensis. In Table I, varieties which may have value in future breeding work are indicated mainly on the basis of whether they are recorded as having inherited the nonfading tendency, fragrance, or attractive foliage.

In addition to the 220 polyanthas listed in Table I, which for want of better evidence we may assume represent the variability possible from crossing derivatives of just two species, we have 64 varieties listed in Modern Roses II as polyanthas but obviously actually hybrid polyanthas. These varieties in other words are the result of crossing polyanthas with other species or with varieties derived from other species. Naturally these exhibit a remarkably wide range of characters and the only features they share with the true polyanthas are the everblooming character and dwarf habit, and indeed some recent varieties can hardly be called dwarf! These as well as the 78 varieties of hybrid polyanthas listed in Modern Roses II may be classified into various groups based on which species, or species complex exerts the preponderant influence. Thus the rather large group of polyanthas X hybrid teas becomes Hybrid Polyantha Class I and is listed in Table II.

Another group of varieties are backcrosses of polyanthas X hybrid teas to hybrid teas. Presumably these should show more hybrid tea influence, as indicated by larger flowers, better bud form and more fragrance than most varieties in Hybrid Polyantha Class I. This group then becomes Hybrid Polyantha Class II and is listed in Table III.

Evidently rose breeders have not considered backcrossing of polyantha X hybrid teas to polyanthas as a very profitable means of producing good new varieties. At least only one variety is listed in what logically becomes Hybrid Polyantha Class III. This variety and parentage is as follows:

It would seem that backcrossing of polyantha X hybrid tea varieties indicated in Table II as having possible value in breeding, to non-fading, fragrant varieties of polyanthas listed in Table I would result in some very fine non-fading fragrant hybrid polyanthas with bud form definitely better than that now existing in the true polyantha group.

A very interesting and complex group of hybrid polyanthas are those involving Rosa Wichuraiana. Some of these are the result of crossing polyanthas with Dorothy Perkins, a variety obtained by crossing R. Wichuraiana X Mme. Gabriel Luizet, a hybrid perpetual; others are the result of crossing directly to R. Wichuraiana. They logically may be classified in a group distinguished from those previously considered by characters inherited from R. Wichuraiana, and become Hybrid Polyantha Class IV, or Hybrid Polyantha-Wichuraiana hybrids. They are listed in Table IV.

Several further developments in this group have produced varieties which might well be included in Class IV because of the marked R. Wichuraiana influence. One of these is Poulsen's Copper which resulted from a cross of Ellen Poulsen with Mevrouw G. A. van Rossem. The bud is long pointed and flower high-centered rose-pink and orange. Unfortunately the fine foliage characteristics of Ellen Poulsen have been lost. Evidently backcrossing to varieties in this class having the desirable disease-resistant glossy foliage is necessary for complete development of this line. The other varieties referred to above are results of attempts initiated by me at the Armstrong Nurseries seven years ago to combine the evergreen, fine foliage characters of a variety in this class, i.e., Mrs. Dudley Fulton, with the miniature flower and plant of R. chinensis minima, using the variety Tom Thumb.

The result has been the development of a line quite unlike anything previously developed, and in fact, quite unexpected when the cross was made. Though some very dwarf plants no larger than Tom Thumb resulted, the really important hybrids were the ones combining the evergreen foliage and large cluster habit of Mrs. Dudley Fulton with an amazing profusion of fine little miniature double flowers. Three of these have now been introduced, two through the Armstrong Nurseries and one through the University of California at Los Angeles. They are named China Doll, Pinkie, and Pink Cascade. Together they form a graduated series as regards height in the order named, Pink Cascade being very broad, bushy and about three feet high. All have fine, soft pink, double flowers, produced in very great abundance on very large clusters. Pinkie, developed by Herbert Swim of the Armstrong Nurseries from China Doll, has very good bud form, making the individual flowers highly desirable for corsage use. The development of this line has been presented in some detail to show the very profitable results of taking already existing lines of development and carrying them even a step or two forward.

Crosses of polyanthas with Rosa rugosa or derivatives of R. rugosa make up Class V. These are listed in Table V. They are all characterized by having large leathery, dark green foliage, inherited from R. rugosa.

An interesting combination is the variety Helen Leenders, a cross of Orléans Rose X Rosa foetida bicolor. This hybrid polyantha might well be used in further breeding work as it should carry the beautiful bicolor orange reverse of Austrian Copper Rose, which is inherited as a recessive, i.e., does not appear in the first generation cross. Two other roses classed as polyanthas but having no polyantha heritage at all as far as can be determined, also carry this recessive factor, namely Tip-Top, a cross of Trier X R. foetida bicolor and Aschenbrödel, a cross of Petite Leonie X R. foetida bicolor.

A very complex hybrid polyantha is the cross of Karen Poulsen X R. moyesi, called Langley Gem. This is actually a polyantha X hybrid tea X hybrid tea X R. moyesi. It has leathery bronzy foliage and even if only partially fertile should be useful in introducing the unique blood red color.

The following group of varieties evidently have no polyantha background at all, neither R. multiflora nor R. chinensis entering into their ancestry. Nevertheless they evidently have certain characters such as cluster habit, which make them similar enough to be classified as either polyanthas or hybrid polyanthas. This indicates that other species of the genus Rosa have either factors identical to those in R. multiflora and chinensis or so similar to them in effects as to be indistinguishable phenotypically. Though this is not an uncommon situation genetically it does create a classification problem well nigh impossible of solution. Nevertheless from the point of view of further breeding work these pseudo-polyantha varieties should be kept separate from the true polyanthas and hybrid polyanthas. In Table VI the characters which evidently led rosarians into classifying these genetically diverse varieties into the polyantha group are noted briefly under the column "Polyantha-like characters."

Finally there is a group of varieties classed as polyanthas and hybrid polyanthas whose recorded parentage is so incomplete as to make it impossible to classify them. These could probably be classified into some of the above groups if grown in a test garden in direct comparison with varieties in other classes. Thus Fluffy Ruffles, a cross of Miss Rowena Thom X Seedling 72, in all probability is in the polyantha X hybrid tea class judging by its appearance. These varieties with their parentage as far as given are listed in Table VII.

BREEDING THE IDEAL POLYANTHAS

The ideal polyantha or hybrid polyantha will of course vary with the locality in which we live. In the eastern and central states, or the corn belt area, the ideal varieties will be very hardy and blackspot resistant. In the western and particularly the milder southwestern states, the main considerations are mildew resistance and a practically evergreen habit. In all localities it would seem that the ideal polyantha should be primarily a good landscape plant. This means it should lend itself to use as a border planting along driveways, at edges of shrubberies, or around the rose garden itself. Also varieties useful for planting in beds to give masses of color are highly desirable. Many of the newer and some of the older varieties fill these needs quite well.

However, from the point of view of ideal types, all leave much to be desired. The foliage should be more abundant and of a glossy leathery type in both the bronzy and dark green colors. It should be unmarred by either blackspot or mildew lesions. Most polyanthas, even the most recent, have flowers which fade too quickly, often to undesirable shades. This characteristic undoubtedly is inherited from the R. multiflora side of the family. By crossing the varieties indicated in the various tables to R. chinensis mutabilis, or to non-fading older polyantha varieties indicated in Table I, this fading tendency can be eliminated. In fact, not only does R. chinensis mutabilis not fade but the flowers actually darken as they age! Crosses I have already made indicate that this very desirable character is readily transmitted. Furthermore, as pointed out by Sgt. Griffith J. Buck¹ (ARA, 1945, p. 85), we can increase the hardiness of our R. chinensis varieties. To develop the foliage we must make liberal use of hybrids involving Captain Thomas as discussed in a previous article (Lammerts², ARA, 1945, p. 71). The polyantha-Wichuraiana hybrids such as Ellen Poulsen (Table IV) may also be very useful in building up foliage characters. The need of very abundant flowering cannot be too strongly stressed. Abundance of flowering depends on (1) the size of individual flower clusters, (2) rapidity with which new clusters are formed, and (3) rapidity of individual flower opening. Many of the newer varieties such as China Doll, Pinkie, and Pink Cascade are ideal in this respect. They need to be developed into other colors with the desirable characteristics mentioned above, i.e., better foliage, unfading flower, and increased hardiness.

As regards colors, we have in several recent varieties some excellent shades. Goldilocks comes very close to being an ideal yellow, though efforts must be continued toward the attainment of the deeper yellow shades. Again, Floradora, though a most remarkable color, varying from Nopal red to scarlet, fades badly and is too tall and stiff in habit of growth to be an ideal landscape plant. This color on an unfading flower, however, and a more dwarf compact habit would be a sensation!

Finally, as always, we come to fragrance, a character many polyanthas, especially the recent ones, are singularly lacking. In the tables listed, polyantha varieties are noted which have been recorded as fragrant. It would seem decidedly worth while to use these in building up fragrance within this group. Of course crosses to fragrant hybrid teas may be necessary in order to introduce enough factors to create really fragrant polyanthas. Much more data on the inheritance of fragrance is needed in order to more intelligently attack this phase of the problem.

Though the attempt made in this paper at a genetic classification admittedly leaves much to be desired, and certainly does not solve the problem of just how we should classify the highly heterogeneous polyantha group, at least a clear idea of its complexity is presented. Obviously we would be unwise to continue listing varieties in Tables II to VII as just polyanthas, and furthermore some workable way of excluding the pseudo-polyanthas (Table VI) from the hybrid polyantha classes is needed. Perhaps we ought to set up for these roses and those in Table VII the terms "large and small-flowered cluster roses" as is done in many nursery catalogues. In fact, the cluster habit is about all these varieties have in common and also share with the true polyanthas and hybrid polyanthas. Only by growing all of these varieties together in test gardens, and making a painstaking study of their characters can a really adequate system of classification be made. If at all possible the genetic distinctions separating polyanthas and true hybrid polyantha classes from the pseudo groups should be recognized, as any system of classification obscuring these distinctive features will increase the difficulties of the plant breeder in selecting the proper varieties for further progress. Basic research on the inheritance of certain complex characters such as fragrance, bud form and disease resistance is urgently needed. Very possibly the research committee of the American Rose Society may be able to interest scientists at state and federal institutions in some of these fascinating problems, the solution of which would so greatly aid rose breeders in attaining the ideals herein set forth. In any event, the field is wide open, the players but few, and the rewards in terms of greater usefulness of the rose very great.

TABLE I

TABLE II

TABLE III

TABLE IV

TABLE V

TABLE VI

TABLE VII