''Rosa'' × ''alba'', the white rose of York, is a

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

rose A rose is either a woody perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred species and tens of thousands of cultivars. They form a group of plants that can be ...

of unknown parentage that has been cultivated in Europe since ancient times. It may have originally been grown mainly for the sweet scent of the flowers, but is now also used as a winter-hardy garden shrub. Cultivated forms have white or pink flowers, and most have many petals. Hybrid cultivars have also been produced with red or yellow flowers.

Description and distribution

''Rosa'' × ''alba'' plants are tall

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

s with arching stems and bluish-green leaves. They bloom only in mid summer. They are extremely cold hardy and disease resistant, hence they are used to create new varieties for

subarctic climate The subarctic climate (also called subpolar climate, or boreal climate) is a climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of an ocean, ge ...

s like northern Scandinavia and Canada. These magnificent shrubs can withstand shade and semishade, and are easily found abandoned in semi wild situations. In

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

and

Finland Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...

the

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

bred 'Minette' has been considered a wild rose called ''R.'' × ''suonum'' (Mustialanruusu). The Mustiala rose belongs to the Finns' tradition of roses "and is unknown outside the Nordic countries, although in 1819 it was bred in France".(in Finnish) article
"Rosa 'Minette' / mustialaros, nordisk ros" via Sanoma News Oy Found alba roses are very common in

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

; some may be local variations, but some could be old cultivars waiting to be renamed.

Parentage hypotheses

''Rosa'' × ''alba'' is

hexaploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

, with six sets of chromosomes in each cell, which means that it interbreeds only rarely with the more common diploid, tetraploid, and pentaploid roses. Maskew and Primavesi concluded in 2005 that a 1993 suggestion by Graham and Primavesi that it was derived by chromosome duplication from a triploid offspring of ''R. arvensis'' (diploid) and ''R. gallica'' (tetraploid) had been mistaken. ''R. alba'' shares some nuclear DNA sequences with ''R. canina'' and may be derived from hybridization between that species and ''R. gallica''.

Alba cultivars

Cultivars of ''Rosa'' × ''alba'' that are still grown include: * Rosa 'Alba Foliacea' * Rosa 'Alba Maxima' * Rosa 'Alba Semi-plena' * Rosa 'Alba' Suaveolens' * Rosa 'Amélia' * Rosa 'Belle Amour' * Rosa 'Blanche de Belgique' * Rosa 'Céleste' * Rosa 'Chloris' * Rosa 'Félicité Parmentier' *

Rosa 'Great Maiden's Blush' ''Rosa'' 'Great Maiden's Blush' is white blend Alba rose cultivar that appeared during the 14th century. It was introduced in Australia by Camden Park in 1843 as 'Maiden's Blush'. 'Great Maiden's Blush' has received the Royal Horticultural Socie ...

* Rosa 'Jeanne d'Arc' * Rosa 'Königin von Dänemark' * Rosa 'Mme Legras de St Germain' Mmeplantier

Hybrid cultivars include: * Rosa 'Mme Plantier', an old rose with feathery sepals and cream flowers fading to white * Rosa 'Crimson Blush', with red flowers, introduced 1988 * Rosa 'Lemon Blush', with pale yellow flowers, introduced 1988 * Rosa 'Morning Blush', white with pink and red edges, introduced 1988 * Rosa 'Royal Blush', with pale pink flowers, introduced 1988 * Rosa 'Tender Blush', with pale apricot flowers, introduced 1988

References

External links

* https://whiteroseshub.com/meaning-of-white-roses/ {{DEFAULTSORT:Rosa alba

alba ''Alba'' ( , ) is the Scottish Gaelic name for Scotland. It is also, in English language historiography, used to refer to the polity of Picts and Scottish people, Scots united in the ninth century as the Kingdom of Alba, until it developed i ...

Hybrid plants