by AtlasMD » Fri Mar 23, 2018 1:47 am
Of course, there are at least the three relatively widely-grown species that repeat as a rule: R. rugosa, R. moschata, and R. bracteata. The musk rose (R. moschata) was introduced to Europe before the China and, long before that, contributed to the hybrid R. × damascena, which has (variably) repeat-blooming sports like 'Autumn Damask' and various other progeny that probably owe any repeat-blooming qualities to its influence ('Stanwell Perpetual', for instance). R. moschata probably didn't gain as much attention for its everblooming nature because in a cool-summer climate like Britain's, it doesn't begin to flower until relatively late in the year, leading to the reported impression that it was "autumn-flowering" (in regions with warm summers, it actually starts as early as most roses and repeats until winter). Whether or not the reported surprise parent of the Damask, R. fedtschenkoana, was really involved, that is another species that can be said to repeat naturally. 'Ross Rambler', which is more of a mystery as far as its species affinity is concerned, is also pretty free with its sporadic flowers, but I think it is likely to be either a pure species or a natural F1 hybrid if its origin story is correct. Some forms of R. arkansana can also be observed to throw occasional flowers long after the main season is over, and some other North American species in Section Rosa (R. carolina, R. palustris) have what seems like an extended flowering that can vary by clone. There are certainly others, but those are some of the ones that come quickly to mind!
Sometimes, even species or hybrids that do not repeat themselves and have no apparent repeat-blooming ancestors manage to give some repeat-blooming progeny when crossed with roses that do: 'Soleil d'Or' would be one example, and I once raised a seedling from a cross between 'Auscot' (ABRAHAM DARBY) and 'Harison's Yellow' that repeated (albeit somewhat slowly) like a modern rose. Maybe there is something about the control of once-blooming in R. foetida and/or R. spinosissima that is particularly easy to overcome with the right partner.
Stefan
Of course, there are at least the three relatively widely-grown species that repeat as a rule: R. rugosa, R. moschata, and R. bracteata. The musk rose (R. moschata) was introduced to Europe before the China and, long before that, contributed to the hybrid R. × damascena, which has (variably) repeat-blooming sports like 'Autumn Damask' and various other progeny that probably owe any repeat-blooming qualities to its influence ('Stanwell Perpetual', for instance). R. moschata probably didn't gain as much attention for its everblooming nature because in a cool-summer climate like Britain's, it doesn't begin to flower until relatively late in the year, leading to the reported impression that it was "autumn-flowering" (in regions with warm summers, it actually starts as early as most roses and repeats until winter). Whether or not the reported surprise parent of the Damask, R. fedtschenkoana, was really involved, that is another species that can be said to repeat naturally. 'Ross Rambler', which is more of a mystery as far as its species affinity is concerned, is also pretty free with its sporadic flowers, but I think it is likely to be either a pure species or a natural F1 hybrid if its origin story is correct. Some forms of R. arkansana can also be observed to throw occasional flowers long after the main season is over, and some other North American species in Section Rosa (R. carolina, R. palustris) have what seems like an extended flowering that can vary by clone. There are certainly others, but those are some of the ones that come quickly to mind!
Sometimes, even species or hybrids that do not repeat themselves and have no apparent repeat-blooming ancestors manage to give some repeat-blooming progeny when crossed with roses that do: 'Soleil d'Or' would be one example, and I once raised a seedling from a cross between 'Auscot' (ABRAHAM DARBY) and 'Harison's Yellow' that repeated (albeit somewhat slowly) like a modern rose. Maybe there is something about the control of once-blooming in R. foetida and/or R. spinosissima that is particularly easy to overcome with the right partner.
Stefan