SCOTS ROSES AND RELATED CULTIVARS OF ROSA SPINOSISSIMA - A REVIEW

‘Scots Roses’ and other cultivars of Rosa spinosissima (R. pimpinellifolia) are less well-known today than other rose groups and an under-exploited genetic resource. However, in 1840, there were probably more cultivars of ‘Scots Rose’ than cultivars of all the other distinct groups of garden roses of the time combined. Hundreds of single, semi-double and double Scots Roses were raised in a wide range of colours in Britain, Europe and North America before 1830. They were less ‘fashionable’ but more widespread by 1840. Immigrants to North America, New Zealand and elsewhere carried suckers or seeds of Scots Roses to their new homes. Most of the old cultivars originated as variants or hybrids of the low-growing form of the species that grows wild in north-western Europe. In the 20th century, Doorenbos in the Netherlands and others raised cultivars with a similar character to the old Scots Roses. However, Kordes in Germany and others used tall-growing Asian forms with larger flowers (e.g., ‘Altaica’) to breed large shrubs (e.g., Frühlings hybrids). Such hybrids have a different habit and character to the old Scots Roses. Depending on latitude and altitude, true Scots Roses bloom between April and July in the Northern Hemisphere or between October and December in the Southern Hemisphere. Some are repeat-blooming. They are very floriferous and generally sweetly scented. Most produce black or dark purple heps. Many exhibit good autumn colour in shades of yellow, orange, pink, red or purple. Few old cultivars remain in commerce but many old garden-worthy cultivars have been rediscovered and new seedlings raised. There is renewed interest in the group but their nomenclature is confused. R. spinosissima cultivars are extremely cold-hardy and resistant to drought and diseases. These charming but tough roses have potential as a source of new garden roses in a time of climatic uncertainty.