Hybrid Brier Roses
A RECENT issue of The Garden contains a colored plate of a group of the hybrid Brier Roses shown in London last year at the metropolitan exhibition of the National Rose Society by the raiser, Lord Penzance, an enthusiastic rosarian and liberal supporter of the society. These hybrids are obtained by crossing the Sweet-brier with various Hybrid Perpetual Roses, chiefly Alfred Colomb, Dr. Sewell and Paul Neyron. The new race is sweet-scented, with foliage as fragrant as that of the Sweetbrier. The color of the flowers varies, however, from light pink to scarlet, and in the Rosarian's Year Book, Lord Penzance reports that " as many as four or five of the seedling Sweet-briers which have hitherto flowered have now turned out to be perpetuals, blooming a second time tin the autumn and blooming then freely. During the autumn of 1891, indeed, in spite of the heavy rains they have gone on blooming right through the month of October, and they bloom, like their seed parent, in clusters. An additional charm, and in my estimation a great charm, is to be found in the fact that these flowers have a very delicious scent—a scent quite independent and different from that of the foliage." From an article by a correspondent of The Garden which accompanies the plate of these charming flowers the following account is condensed:
Many lovers of the Rose will call to remembrance the collection of hybrids of the Sweet-brier and other types Lord Penzance sent to one of the meetings of the Royal Horticultural Society in June, 1891, and later to the Rose show held at the Royal Aquarium. They illustrated in a remarkable degree the possibilities of cross-breeding in Roses, in which work his lordship has proved eminently successful.
In a paper contributed to the Rosarian's Year Book for 1891, Lord Penzance asks, How do these modern Hybrid Perpetuals comport themselves in the garden? He answers his own question, by saying, "We all know how hard it is to make a lovely object out of a standard Rose, and whenever this is done it is achieved only by a very careful and skillful use of the pruning-knife. But, take the dwarfs. Do they form themselves into what used to be known as a Rose-bush; or are they not given to exhibit a straggling, unequal growth, one or two shoots breaking up from the crown or the lower part of the plant and robbing the life from the rest? If cut back hard in the spring the plants become a stumpy, somewhat insignificant and not a very captivating object. If subjected to what the French call the 'taille longue,' they are apt to become leggy and shabby in the lower branches. Here, again, there is no doubt but that a good deal may be done by skillful pruning, but the growth of the plant does not lend itself readily and naturally to the formation of an even head or symmetrical bush." It must be admitted there is much truth in the foregoing remarks.
Lord Penzance is of opinion that the gift of autumn-flowering of the Hybrid Perpetuals comes from having been crossed with what he calls the Eastern Rose—the Rose de Bengale of the French. The comparatively scanty bloom of many of the Hybrid Perpetuals, and the contrast between the old summer Roses and the modern Hybrid Perpetuals are very striking. The old summer-flowering Roses are covered with bloom in their season. I saw a striking instance of this in an old garden at Enfield during the past summer. A path, arched with wire trellises, had been covered years ago with the old-fashioned summer Roses, and at the time I saw them they were in grand bloom; indeed, in such happy plenteousness, as to form a floral sight worth going miles to see, but the gardener, knowing the fleeting character of the Rose-bloom, had wisely planted, among the Roses, Clematises and other late summer-flowering subjects to carry on the floral succession until the autumn. Lord Penzance points out that the class of Roses known as Hybrid Chinas and Hybrid Bourbons, none of which ever bloom a second time in autumn, put forth a sheet of bloom in every part of them during the summer with a profusion which it would be difficult to name half-a-dozen Hybrid Perpetuals capable of emulating. Two more well-known defects in the Hybrid Perpetuals are mentioned. They are destitute of fragrance, and "many, if not most of them, are short-lived." It was the existence of these defects in our most popular class of Roses which induced Lord Penzance to try if something better could not be produced by working upon new lines. Recognizing the fact that the races or families of the Rose are capable of combining by cross-fertilization, his lordship entered upon a line of action of his own with the object of securing a new Rose which might be free from some of the existing defects. The Sweet-brier was selected as the natural basis of a new race. In the first place, it is indigenous to the soil and climate; it is proof against the most vicious attacks of our English winters; it is superior to the weakness of mildew, and as little subject to the troubles of the Rose as any other species. It is a prolific seed-bearer, and "more certain to bear fruit when fertilized with pollen of other Roses than any Rose or class of Roses that in my limited experience has presented itself."
Some interesting facts are noted. The seedlings obtained by impregnating the Sweet-brier with foreign pollen had a remarkable strength of root and growth, and struck readily from cuttings. The sweet-scented foliage of the Sweet-brier was also produced. A complete cross was obtained between the Sweet-brier and the Persian Yellow, the bloom larger than that of the Sweet-brier, pale yellow in color, and the foliage fully as fragrant, if not more so. The Austrian Copper, crossed on to the Sweet-brier, produced a seedling, the bloom not quite so deep in its color as that of the pollen parent, yet a close copy of the original, with the sweet scent of the Brier diffused in its foliage. The pollen of the Hybrid Perpetuals, the Hybrid Bourbons and the Hybrid Chinas, put upon the Sweet-brier, produced distinct crosses—distinct in the sense that the wood, foliage, habit of growth and the thorn are not those of the Sweet-brier.
"Among hundreds of Sweet-brier seedlings," says Lord Penzance, "which are evidently crosses, I have had only one that did not retain the sweet foliage of the seed parent, and as to this one I cannot help thinking there must be some mistake as to its parentage." All attempts to cross the Sweet-brier upon the Hybrid Perpetual have failed to produce scented foliage, but the seedlings so obtained have been small, and Lord Penzance is not by any means hopeless of attaining this result.
So far the blooms of the Sweet-brier seedlings show but little tendency to doubleness. Lord Penzance states that none of them as yet have given him more than two complete rows of petals. It is his desire to secure a greater degree of doubleness, and he hopes to succeed in another generation or two of seedlings. With this end in view, it is his intention to cross them again with the pollen of Hybrid Perpetuals, Hybrid Chinas and Hybrid Bourbons. Other crosses have engaged, and still are engaging, the attention of Lord Penzance, such as the Moss Rose, Cellini, with the Musk Rose, Fringed Musk, which he has secured; the joint characteristics of the progeny are unmistakable. Monsieur Crépin, the distinguished authority on the botany of the Rose, pronounced it to be a distinct hybrid.
One difficulty in the way of the cross-fertilization of Roses is to procure "the pollen required at the right moment. The time at which, and during which, the stigmas of the flower to be operated upon are mature and fitly receptive is very uncertain and of short duration. The same thing is true of the anthers, and the liberation of pollen, and this makes an opposite combination between the stigmas of one race and the pollen of another no easy task." But in the course of his operations Lord Penzance has discovered that the pollen of the Rose can be kept in full vitality if preserved from all moisture or damp for many weeks—in short, from one end to the other of the hybridizing season—and in his experience the preserved pollen may actually produce a larger proportion of seed than the pollen fresh from the flower. Not that it is to be understood that preserving pollen adds to its fertilizing power, but that "it can be applied to the stigma of the seed-bearer in much fuller quantity and much more handily and adroitly than can be done with the fresh. When the pollen bursts from the anthers in the first instance it very often breaks forth in small quantity only, and the supply of it is at times apt to fall short in the midst of an operation." Then ripe pollen is not always obtainable when the flower to be dealt with is exactly fit for the work, and there is a temptation to take the pollen before it is fully ripe.
It must not be supposed all the crosses made by Lord Penzance have succeeded. He has failed with the Boursault and Microphylla types; also with Rosa Sinica and the Macartney Rose, but there is the right ring in the resolve with which his lordship concludes his interesting and instructive paper when he says, "I have hitherto been vanquished in these attempts, but I shall not give them up until I have received a good many more rebuffs."