Hi Jim,
Can you give us some more details, please? Was there good color and were the blooms at all double?
Paul
If you grow out self seedlings of Mutabilis some will be semi-double. I also have Amber Cloud x ‘Buttercream’ (China) coming along now.
I haven’t used such in breeding despite being in deep south where they are among most reliable of roses. My concerns were the twiggy growth, thin stems, and, to my eye, somewhat unattractive foliage. I think you could get some great landscape plants, but wonder how far along you would have to breed before anything marketable comes out of it.
Chinas do get BS, but shrug it off here in BS central. While rarely a concern, mildew is problematic even down here for many of the cultivars. Crossed with something more evergreen, I wonder if the shrugging-off ability might be compromised.
They have produced some nice first generation plants crossed with musk derivatives. There is, in particular, a Mutabilis descendant which inherited the mutable color change which intrigues me. It would be nice if the deepening-in-the-sun color trait were freely inherited in offspring.
I have had some good results using Mutabilis as a pollen parent. I don
Ten years ago when I restarted breeding more intensively I hybridized with Chinas as I admired their hability to “build up” over the years. Slaters, Parson’s, Semperflorens (aka Sanguinea), Mutabilis, Perle d’Or i.e. are seen as dense masses as big as 2m high and wide in old for decennies abandoned gardens here french Riviera. Some being centuries old.
And it is a quite varied group. Not uniform at all. They just have no modern character. Rather slow starters and disliking to be pruned.
It is a breeding alley I follow no longer.
First if these plants are very very desease tolerant and rebound easily when hit, when conditions are bad they are BS and PM succeptible. There are better desease resistance sources.
Second IMO Chinas contribute little if any new features to modern roses as being allways among the ultimate ancestors. There are better sources for different characters.
Third the triploids I got crossing them with modern vars were far from something marketable and fertility allways reduced to poor. Even the fertile triploid produce few seeds that too often germinate and grow poorly.
Combining them I did not explore enough.
A thing I learned for sure they never self. Left alone they never form hips. OP hips are only produced when there is compatible pollen available as well as pollinators. Given both they all are quite fertile both ways. They have to be pollinated as soon as opening. The bigger the seeds (Sanguinea, Mutabilis) the more difficult to germinate. Sanguinea and Mutabilis hips usually fall before maturity.
Slater that is apparently the ancestor of most red cvs is not the easiest and its progeny fertility is not high.
Old polyanthas often mildew and dislike alkaline soils as do multiflora. And I suspect most to be virused. The seedlings are often stronger than the progenitors.
Sanguinea that if I remember well was little used is probably the best China route for red diploids. If exposed to late frosts its otherwise abundant pollen development may be hindered. With its large hips and seeds it is closer than the others to the chinensis-gigantea complex.
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Powdery Mildew seems to be endemic to most of the early diploid Chinese cultivars and species for some reason. I’m finding it the hardest thing to breed away from.
Thanks for these insights Pierre. What you’ve said about old polyanthas is absolutely. Most are chronically chlorotic here.
I’m sure we are only the latest generation to try to make something from new from something old. Still we have some new tools at our disposal and new species are being integrated.
Hope springs eternal.