Silver Moon (Wichuraiana Climber) [R. wichuraiana x Devoniensis) x R. laevigata]

ADDISONIA 2(4): 61-62 (December, 1917) (Plate 71)
"Silver Moon" Rose

A vigorous bush with long climbing stems, glossy dark green foliage, and large white partially double flowers. The stems attain a length of a dozen feet or more, and are armed with red spines which are compressed and somewhat recurved. The stipules are adnate to the leaf-rachis, have spreading acuminate free tips, and have the margins with stalked glands. The leaf-rachis, usually more or less tinged with red, bears a few spines, similar to those on the stem but smaller, and rather numerous stalked glands. The glabrous leaflets, which are commonly five, the lateral on stalks an eighth of an inch long or less, the terminal on a stalk much longer, are ovate to nearly orbicular, up to two inches long and an inch and three-quarters wide, and are abruptly short-acuminate; they are lustrous dark green above, paler beneath, the margins crenate-serrate with pointed teeth, usually fifteen to twenty-five on each side. The flowers are borne in clusters of usually two to four, the stalks, which are tinged with red, with stalked glands. The sepals are ovate, acuminate into a long tip, the margins entire or rarely toothed or lobed, the outer surface on the margins and the entire inner surface hairy. The buds are pointed and well-shaped, of a creamy yellow, opening into large flowers, sometimes five inches in diameter, of a pure white sometimes faintly tinged with yellow; the outer petals are broad and spreading, the inner smaller, undulate and incurved, partially concealing the central mass of bright yellow stamens, the whole producing a flower of charming beauty.

This rose was originated by Dr. W. Van Fleet, phsyiologist in the Bureau of Plant Industry, at Washington, D. C. In response to an inquiry Dr. Van Fleet writes as follows: "The climbing rose Silver Moon was raised in 1906 from an unnamed hybrid of Rosa Wichuraiana x devoniensis pollinated with the Cherokee rose (R. laevigata). I have grown many seedlings of Wichuraiana (type) x Cherokee, but none turned out as hardy and showy as Silver Moon. The influence of devoniensis, a large white-flowered and quite hardy form of Rosa odorata or Tea rose, appears to have been highly beneficial in the case of Silver Moon, though the direct cross of Wichuraiana and devoniensis has little merit as a garden plant, as it is a shy bloomer, but vigorous in growth and with good foliage." Dr. Van Fleet adds that Silver Moon bloomed the second year from seed.

It would appear from this that Rosa devoniensis has been the blending element, harmonizing in "Silver Moon" the best in Rosa Wichuraiana and Rosa laevigata, giving us in this production of Dr. Van Fleet a rose which holds a unique position among the climbing roses hardy in the north; for it adds to our gardens one with all the beauty and attractiveness of the Cherokee, not hardy in this latitude, combined with a vigor which defies the rigors of our northern climate. The large semi-double flowers and lustrous deep green foliage make it a striking object anywhere.

It was shown in 1908 at an exhibition of the Horticultural Society of New York held in the Museum building of the New York Botanical Garden. With the permission of the exhibitor the material exhibited was made into cuttings, and it is from this source that the plants at the New York Botanical Garden have been derived. The illustration was prepared from one of these plants.—GEORGE V. NASH

DNA evidence suggests that R. laevigata did not participate in the cross, which probably makes 'Silver Moon' an F2 seedling from R. wichuraiana x Devoniensis.