Rosa davurica Seeds | Amur Rose
LATIN NAME: Rosa davurica
COMMON NAME: Amur Rose, Dahurian Rose
Plant Profile
The Amur rose takes its English name from a river and its scientific epithet from the Daurian country, the rolling Transbaikal steppe where it was first collected. It is one of the roses that made the northern scrub worth crossing: through early summer the bushes carry an open display of single pink flowers, and from late summer into winter the same bushes hold a heavy crop of red hips that outlast the leaves. The plant is a survivor of the coldest inhabited part of the rose range, and that hardiness is the reason breeders keep coming back to it.
The hip is the rose fruit: a fleshy, urn-shaped receptacle that encloses a mass of hairy achenes. In this species the hips colour early and stay firm, which makes them a food source for birds and a winter-long accent in the garden. Plants of the Far East and Transbaikalia ripen a crop rich in ascorbic acid, and that chemistry, rather than the flower, is what most of the plant research has addressed.
The genus Rosa is arranged in sections, and this species belongs with the cinnamon roses, the group that includes the rugosa and the cinnamon rose of European gardens. Its distinguishing characters are the paired nodal prickles, the smooth receptacle, the five to seven leaflets and the erect rather than suckering habit. Within the Far Eastern flora it overlaps with the rugosa rose on the coast, and the two are easy to separate in the field: the rugosa has wrinkled, heavily veined leaves and very bristly stems, while the Amur rose has smooth foliage and clean, well-spaced prickles.
Garden roses are mostly hybrids of a handful of species, and hardiness has repeatedly been brought in from wild Asian and Siberian parents. Rosa davurica has been used in breeding work aimed at shrub roses for cold climates, because it survives winter temperatures that kill most garden cultivars, and it passes on a compact, erect habit and a heavy hip crop. Its one fault as a parent is that the single pink flower is not the double, repeat-flowering form that most gardeners want, so it is usually used as a link in a longer pedigree rather than as a direct cross.
Science & Biotechnology
Rose hips are among the richest plant sources of ascorbic acid, and the red coat that gives the fruit its colour comes from carotenoid pigments, with lycopene and beta-carotene both reported from the hips of wild Asian species. The same tissue carries flavonoids, mainly glycosides of quercetin and kaempferol, and the achenes inside are oil-rich and hairy, which is why a hip should be sieved before it is used. The combination of acid, pigment and flavonoid is what makes the hip syrup of northern Europe and northeast Asia such a strong-tasting preparation.
Rose seed is not merely slow, it is double-dormant. The achene wall is hard and impermeable, and the embryo inside needs a warm period of maturation before a cold period will finish the job. The practical sequence is to extract the achenes from ripe hips, mix them with damp sand or vermiculite in a labelled bag, keep them warm for a season and then move the bag to a cold frame or a refrigerator for a winter. Clean the pulp away first, because it contains substances that hold dormancy in place, and be prepared for seed from the same hip to come away piecemeal over more than one season.
Uses & Benefits
The Amur rose spreads by suckers on its own roots, which makes it an effective informal hedge on a rough boundary where its thorns keep stock and people at a distance. Planted in a row a metre or so apart on a bank, it will knit together in a few seasons and need almost no attention beyond occasional cutting of the oldest stems. It is also a useful wildlife shrub, giving cover through the summer and a hip crop in the lean months, and it holds a dry, free-draining slope where little else will grow.
Growing from Seed
This is an erect deciduous shrub, usually under a metre and a half, whose arching stems carry slender, straight or slightly curved prickles, characteristically in pairs at the base of each leaf. The leaves are pinnate with five to seven leaflets, each oblong and sharply toothed, glossy above and paler beneath, with a pair of stipules fused to the base of the leaf stalk. The solitary flowers are pink, five-petalled, with a ring of prominent stamens, and they sit on smooth receptacles rather than the bristly ones of the rugosa roses. The hips are flask-shaped, smooth and bright red, and they persist on the bare stems well into winter.
A wild rose fruits on wood of the previous season, so the pruning programme has to protect the young stems. Cut out the oldest, darkest canes at ground level after flowering and leave the current year growth to ripen and carry next season fruit. Shortening the tips of long canes to about half their length keeps the bush from whipping about in wind without removing the fruiting wood. Feeding should stop by midsummer, so that the new growth hardens before winter rather than sitting soft on the plant.
Our Take
I grow this one for the hips and for the fact that it never needs spraying. Sow the achenes fresh, keep them cool through the winter, and expect a few seedlings rather than a full row. Gardeners who want the same fruit colour on a tidier shrub should look at our pages on the red rugosa rose and the burnet rose, while the wild roses of wet ground are handled on the swamp rose page.
Related Reading
Gardeners who grow Amur Rose often pair it with these related subjects: