Rose Annual pp. 169-170 (1914)
G. M. Taylor

Rosa laxa, introduced by Retzius in 1803, is a native of Northern Asia, and more particularly of the Siberian portion of that continent. It is classified by Professor Crepin under Section VII.—Cinnamomea—of his scheme, and is associated there with several Asiatic species, notably R. cinnamomea, R. davurica, R. Alberti, R. macrophylla, and R. Beggeriana.

I do not know how long R. laxa has been used for budding purposes, and I cannot remember having seen any notes upon its adaptability for this work. There can be no question, however, about its value as a stock, and as a rooting medium for Roses that must be grown upon light soils it seems to be invaluable. My observation of this species of Rose is very limited, because I have only studied it for three years, but what I have seen of it convinces me that its use might be largely and profitably extended, especially on light soils.

R. laxa under cultivation over a period of three years has only attained a height of three feet, and in July it bears solitary white flowers, with just a suspicion of yellow at their base, and these are borne on very short peduncles. The foliage is doubly serrated, and is shiny above and pubescent beneath. The stems are slender, light rich green in colour, and thorns are somewhat scarce. It seems to breed absolutely true from seed, there being practically no variation from the type in a break of seedlings planted out for budding purposes.

The root system of the plant, however, is its most valuable asset to the Rosarian, and the results from its use as a stock are highly satisfactory. The roots of the laxa stock are very vigorous and strong, and will search far for food. On light, dry soils where Roses have to stand for several years as cutbacks it seems to me that laxa is the best stock for this work. Many Roses, more especially Hybrid Teas, seem to thrive and flourish well in comparison with those worked upon the Seedling-Briar, and the growth is stronger and the flowering period more constant and prolonged.

In my own tests in a small way on a very light soil the plants worked upon Briar have made a very poor show alongside control plants upon laxa.

The Royal Horticultural Society made a small trial of Roses upon laxa stock at Wisley last year, and the soil there is of a very light character. I understand Mr. Wright, the superintendent of the gardens, was highly impressed with the result, and a further and more exhaustive trial will be made there this year. I have no hesitation in recommending this stock to the amateur, and those who must grow their Roses upon light soils should experiment with a few budded upon laxa for themselves.

CybeRose note: This is probably Rosa laxa Hort. rather than the true R. laxa of Retzius.