In 1938 I began using pollen of Rosa nitida on various mother plants in an effort to secure new types of hardy roses. Among the mother plants used was Hansa, the well known Rugosa hybrid, which may possibly have General Jacqueminot as its other parent. From this cross seed was abundant but germination was relatively poor and only a dozen or so seedlings were obtained. Most of these were single, but two doubles attracted my attention: One was such a good rose that I named it Aylsham, after a neighboring town. The description of this variety, as it appears on page 172 of the 1947 American Rose Annual, is as follows: "Stature of plant intermediate between the two parents, stems slender, with a tendency to recumbency. Flower stems slender and weak. Flower a deep pink, approaching red, free of the violet tones of Hansa, very full, with more petals than Hansa and much tidier in form, a little smaller. Foliage similar to Rosa nitida but larger and with less autumn coloration. Blooms once in June. Completely fertile."
This one was considerably the most attractive, of good form for a hardy rose and pleasingly full. The other was second to it, a little less double and a little less deeply-colored. I gave it a number instead of a name, Nitosa No. 2.
I was so well satisfied with the results of this experiment that I repeated the cross and also backcrossed Aylsham with its parent Hansa. In 1947 the plants from these crosses, some 60 in number, began to bloom. Of the repetitions, it is surprising that about half were double. Of these, all were as good as the numbered selection originated earlier and some were better. One was a decidedly small rose and several were average pink to pale pink. It has been a little difficult to judge the color accurately, since all roses opened in extreme drought and heat last year and did not have their full color. The foliage was rather uniform, shiny like R. nitida and closely resembling that of Aylsham in general characteristics. The habit of the bushes differs somewhat, one being recumbent and only a few being more erect than Aylsham. Some of them were remarkably vigorous although this characteristic varied greatly. One produced a few blooms in the fall.
The backcrosses were disappointing. Although the color was generally deeper than in the first-generation hybrids, the flowers were smaller and much sparser. Was this, possibly, the result of inbreeding? I have repeatedly made backcrosses of Hansa and another of its hybrids, one with Rosa Macounii, a native of Saskatchewan, and have noted that these, too, appear to be remarkably sparse in bloom on the average. I am now sufficiently wary of backcrossing to seek more promising lines of effort in roses in the future.
What are the possibilities of Rosa nitida in direct crosses with hybrid teas, hybrid perpetuals and similar roses? The question interests me extremely. Unfortunately, I cannot test it, for the half-and-half hybrids would surely be too tender for my 60 below zero climate. Somehow, I have had very limited success with using hybrid tea pollen on our hardy roses; few hips were produced, and of the seeds obtained, only a few have germinated. My best successes to date have been in crossing our hardy roses among each other. The cross of Betty Bland with Tetonkaha and sister roses is a promising one. The seedlings from this cross would be about one-eighth Rugosa, one-quarter Macounii, one-quarter Blanda, and three-eighths hybrid perpetual. In general, Betty Bland is a very good parent; however, my purpose in this account is not to help anyone make further crosses among the hardy northern roses but, if possible, to interest persons south of me in the possibilities of Rosa nitida as a parent of future roses of the general type of the hybrid tea. The first generation crosses would most certainly be too near Nitida but further dilutions might result in a happy series of combinations. They might tend to inherit weak stems but the colors would probably be red and pink without much violet in them. The shiny leaf and the beautiful autumn coloration would be acquisitions, even if these alone and no particular hardiness were carried across from the native rose.