My RDxS cuttings take is about 20-30%. Great thing is they were planted outside when less than a year old and had no problem with winter. They take awhile to start blooming.
I‘ve had one success pollinating as seed parent Skinner’s Butterball to germination (below zero).
The ones l list all produce abundant big seed laden hips and are in my garden. But “biggies” is operative word. I give pimps and spino cases as he carried both.
Ask about Knud Pedersen’s repeating pimps. They are prizes in my book - small and tidy so far. HMF has a list.
Erskine’s (of the Big 5), Prairie Peace created a stir in Europe so l am told, should probably see if he will save you one. In my books one of the beauties for bloom and color. Again a “biggy” but with the bloom color all the better.
I also like his single Madeline’s Choice … pale apricot / pink blend … also a biggy.
Ross Ramblers - there a number of them 1,2,4 etc the fully double slays using no techno jargon. A beaut fully double white is the one l have. Either 1 or 4. Not usually listed as spino but ask if he has one. Some say laxa etc. again a biggy.
Suzanne if you got an acreage. Or willing to aggressively prune - l do for all my spinos after 5-7 years. It seems to show up in crossings including my favourite spino hybrid (RDXS) you are cloning. So it canbe crossed.
Good idea to get this Suzanne hybrid rose around the States so talent can try and get its shrub rose quality with hardiness into more roses. I understand, a major Canadian nursery has ceased sending to States after years because too many bureaucratic delays and paper work issues of late. Like Pickering ‘s complaints - as on its last legs. But as per hint by Dr Z and my own experience not an amiable seed parent - see my RD x S crossing table cut l gave you in this thread.
Dr. F L Skinner by Simonet is yet another biggy and the only one l have, beside Anja, that has a bloom mimic of a HT (Joanna Hill × Altaica) . Apparently breeder had no success with carrying on to F2’s. See HMF references. I have challenges with it coming out of winter and thrips like the blooms. A local “Zoo” one is somewhere between 10-12 feet high. However it shows crossing modern with altaica can work.
As l mentioned if he has “Knud Pedersen’s” repeating pimpinefolia / spino examples and if l was an American - SO is - I would speed burn a trail to his place. He will know them. I have a couple and they stay small for me and bloom well e.g. Peter Boyd, Blushing Love etc…
Mon Amie Claire (sic?) is a good one by a Belgium. Small, tidy, and non-stop bloomer in my garden.
Again, another generalization my spinos are hip / seed mad for O.P.s but have not spent enough time trying for more crosses - just a time thing. Ones done this year in stratification at below zero. BTW it is observing spinos seedlings and winter behaviour that re-enforced for me to go just below zero in stratification
Single large white bloom to left centre in Ross Rambler #1 is white R. altaica. A favourite for breeding tries due clean white, large single bloom - still waiting for germination success. Some lump R. altaica under spinos … I do.
Margit might suggest looking for types in his garden.
I hope these pictures down load - not into 5 edits plus - buff photo is a Kordes spino cross Anja that’s actually hardy so far. Beg for that one if there as bloom form and color should be useful if it crosses.
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