Journal of Heredity, 20:304-307 (1929)
Rosa Gigantea And Its Hybrids
H. Cayeux

Director des Jardin et Promenades de la Ville der Havre, France

Rosa gigantea
from Journal des Roses, Aout 1905

Belle Portugaise
Etoile de Portugal
from Journal des Roses, Aout 1905

This magnificent species, introduced almost forty years ago, seems to have been cultivated some time before producing its large and beautiful flowers, for it was not until April 1896, when I was director of the Botanical Gardens of Lisbon that it bloomed for the first time in Europe. The following year, a plant received from the Botanical Gardens of Kew several years before, produced a number of roses at the home of Baron Soutellinho at Porto (Portugal).

Up to this time, Rosa gigantea had been considered, and rightly, as a shy bloomer. The reason for this was that all the specimens then cultivated came from seed which developed so vigorously as to produce stems from 8 to 10 meters (26 to 33 feet) long in a single year. As a result of this, they bloomed with difficulty.

Since then grafting has been resorted to with satisfactory results. By using only flowering branches for grafting wood, the abundance of the blossoms has been considerably increased—so much so, that every plant propagated by cleft grafting upon Rosa indica, for instance, produced numbers of roses as early as the second year.

Plants which are still more generous bloomers can be obtained by top grafting Rosa gigantea, in the same manner upon Tea-roses which have been grafted on the Eglantine rose. Plants thus obtained, cultivated in large pots, make a bushy growth and flower abundantly, although attaining a height of no more than 1.20 to 1.50 meters (46 to 58 inches). I will add that formerly I used this method of cultivation in order than I could have at my disposal small plants, which permitted me to prepare the flowers easily before being hybridized, without having to use a stool or ladder.

On account of the dimensions of the flower, which normally reaches from 12 to 13 centimeters (4.5 to 5 inches) in diameter, and the more or less deep yellow coloring of its very long bud, Rosa gigantea at once attracted my attention, and I thought it would be capable of producing interesting hybrids. It was, therefore, with this idea that I tried a large number of pollinations of this species, using the pollen from various varieties of Tea roses and Hybrid Perpetuals.

Experience has since taught me that the best result is obtained by using pollen of the Tea rose. There seems besides to be more affinity between this and the R. gigantea than there is between it and the Hybrid Perpetuals. In every case the influence in these crosses acts in a satisfactory and dominant fashion.

Early Hybrids

Although the first flowering of R. gigantea took place in 1896, I did not begin the hybridizations until 1898, when I obtained some seeds which, planted in 1899, produced plants whose first flowers did not appear until 1903, four years later. I confess that this period of four years of waiting seemed to be very long; but there is nothing surprising about it if one considers that the seedlings produced by R. gigantea are so vigorous that they must reach a considerable development before deciding to bloom. It was from this series that I had the satisfaction of seeing the beautiful Etoile de Portugal appear, which performs wonders when cultivated in a climate where orange trees grow.

I then tried the reciprocal cross, that is to say using R. gigantea as father, with the aim, above all, of obtaining hardier plants, capable of cultivation in a colder climate, thanks to the use of the varieties employed as mother plants.

From these diverse crosses a series of interesting forms has appeared, among which is found the magnificent variety Belle Portugaise.

The first hybrids of R. gigantea were grown under the skies of Portugal. They came from two different sources, according to whether the latter served as mother plant or as pollen bearer, and may be classified in the following manner:

1st: Rosa gigantea on Tea.
2nd: Tea on Rosa gigantea

Descending from the first cross, the variety Etoile de Portugal is the produce of Rosa gigantea x Reine Marie-Henriette. This plant bloomed for the first time in the Botanical Gardens of Lisbon in 1903. It is of luxuriant growth and seems to have inherited from Reine Marie-Henriette its great abundance of flowers. The elongated buds are often borne by twos or threes on the same flower stalk. The blossom is large, full and fragrant, of a lustrous carmine rose color, shaded to yellow at the base of the petals, which become a lighter color when in full bloom. It should be grown in a temperate climate if one wishes the plant to reach its maximum development and produce in abundance its masses of flowers, of such brilliant and delicate coloring.

The Reciprocal Cross

The second cross, that is to say, the Tea rose x R. gigantea, produced several very excellent and beautiful hybrids, chiefly characterized by their soft coloring, their great profusion of blooms, and their greater resistance to cold. Among these we may especially note:

Named for Alberto Lopes, a Portuguese acquaintance of Cayeux’s who had raised hybrids of R. gigantea using 'Rêve d'Or' and Général Jacqueminot' as seed parents.

1st. Amateur Lopes, from Mme. Bérard x R. gigantea. Flower very large and full, pale salmon, washed with rose-lilac at the tips of the petals. A very floriferous plant of average vigor.

2nd. Belle Portugaise, from Souvenir de Leonie Viennot x R. gigantea. A large and beautiful rose of very delicate coloring—shell pink touched with salmon. The very long buds reach a length, sometimes, of 10 cm. (4 inches), especially when they are produced at the ends of vigorous branches. The flower, when completely open, may measure from 15 to 16 centimeters (6-6.5 inches) in diameter. Grown in a temperate climate, Belle Portugaise attains a great development and is literally covered with its large blooms. It seems to have inherited the great luxuriance possessed by the mother plant, Souvenir de Leonie Viennot; moreover, it is able to produce fertile seeds, and might thus be very usefully employed in hybridization.

3rd. Dona Palmira Feijao, from Souvenir de Leonie Viennot x R. gigantea. Flower large, very full, shell pink in the center, the outside of the petals bright carmine. Very brilliant coloring.

4th. Lusitania, from Souvenir de Leonie Viennot x R. gigantea. Flower large, very full, yellow washed with carmine; bud very long. Plant very floriferous.

It is recommended that these very vigorous plants be used in gardens for covering high walls or trellises, but they do wonders in decorating pergolas and even better when planted by themselves on lawns, provided always that sufficient space is afforded for them to attain their normal development. Under these conditions, the hybrids of R. gigantea present plants of the highest ornamental interest, giving abundant blooms each year. I cannot recommend their cultivation too strongly to connoisseurs of roses; certain as I am that they will give complete satisfaction.

Journal of Heredity, 20:308 (1929)
Other Gigantea Hybrids
B. Morrison

In the American Rose Annual for 1924 Mr. Alister Clark records a few of his experiences in crossing Rosa odorata gigantea. For Victoria, Australia, the enormous growth of this plant is no particular disadvantage, but it was not for this characteristic as much as for its disease resistant foliage and its obvious suitability for his climate, that he valued it and wished to use it as a parent of a new race.

Not all of the parentages are reported, but most of the seedlings are of two classes, direct crosses in which Rosa gigantea was the seed parent, and secondary crosses in which these seedlings are the seed parents. Flying Colours, single light red; Harbinger, single soft pink; Kitty Kininmonth, semi-double, pink; Squatter's Dream, semi-double to saffron yellow represent direct crosses. Lorraine Lee, double rosy apricot-pink; Mrs. Frank Guthrie, semi-double flesh color, are examples of the second group. Golden Vision, Maréchal Niel x Rosa gigantea, semi-double yellow fading to white is the only seedling reported in which gigantea appears as a pollen parent. Undoubtedly there are other seedlings from this type which have not yet been reported in this country.