I’ve been wondering lately about how the choice of understocks for Teas affects their growth, particularly in autumn and winter??? Tasmania is one of the few places in Australia where most roses go fully dormant, but I have a few Teas that don’t. These have always been the own-root ones. They hardly even lost any leaves and some, like Comtesse de Labarthe even continued to flower through winter. The grafted ones, on Dr Phooey or multiflora, all went completely dormant and completely leafless. I started wondering if it was the understock that was going dormant that was causing the top half to also go dormant. I have not tried any experiments to test this… it’s just a hunch. I have ‘Indica Major’ growing here, which is a traditional understock for Teas in Australia, but it too goes dormant and leafless here in the winter. I have grown its OP seeds and they germinate very easily. Has anyone else seen anything like this? Do you think a worthy breeding goal would be to try and breed an evergreen understock plant for Teas and other evergreen roses in mild climates? I was thinking about putting Rosa longicuspis pollen onto ‘Indica Major’ this year to see how that turned out for this job as longicuspis seems to be pretty much evergreen here, is super vigorous, and strikes like a weed with a root system like a willow (i.e. strong and gets into everything!!!). I’m in two minds about it though because I’m an own-root person… but then again, maybe it would be good to have as an option…
Someone with more biology-knowledge will have to answer the question of dormancy. Back when I studied biology, it was assumed that ABA initiated leaf drop and was fully instigated from within the leaves, but I think that has been largely disproved. Regardless, it might be reasonable to think that some phytohormone from elsewhere in the plant could trigger the localized action, and perhaps root stock could influence that activity.
But yes, new root stocks could be a desireable thing, I should think. In the southern U.S., R.x fortuniana is favored. Perhaps banksia might be a good option for you in your crosses for such?
I wanted to try R. canina x R. banksia lutescens at one point but I never got around to it. I wanted to know if Banksia would halt the sucker production of canina while adding thornlessness and nematode resistance. Likewise, I wanted to see if Canina could add some girth, soil-type tolerance and hardiness.
My guess is that it would have resulted in genetic breakdown as seedlings just like the canina/multiflora types did 
Hi Simon,
I don’t recall what rootstock Alister Clark used for his roses. Maybe in the book about his roses? (Mine is still packed away due to moving)
Rod
G’Day Rod, I’ve got the book and read it… no mention of his choice of understock. Are you still in QLD?
Hi Simon,
Was in Port Macquarie, now in Griffith.
Saw a book on Alister Clark’s ‘ladies’ (those he named roses after) in the bookshop the other day (not currently affordable at $50 though),
Do you have R. fort? May be worth a try as it appears to be almost evergreen?
Rod
Port Macquarie huh… don’t know why I thought QLD then… Your roses will enjoy the move to Griffith
I’ve tried ‘Fortuniana’ here before and failed with it. It struck and grew roots and then sat there and did nothing when put in the ground… don’t think it likes Tas much.
My AC book is “A Man of Roses” which is more a documentary account of his family and him as a person. It doesn’t discuss his rose breeding strategies much.
Jadae, I think I recall years ago that Tom S. had a banksia/rugosa cross, which I wondered about as a root stock. (Maybe it was a palustris/rugosa, come to think of it…) Anyway, I remember thinking it might have tolerance of multiple soil issues, coming from two roses of very different cultivation requirements… Dunno if Tom will see this, or if he ever experimented with such as a stock.
I always wondered about that combination also! I also wondered about using banksia with one of the rugosa/multiflora hybrids out there. Rosa california also intrigues me because it is supposed to have one of the highest pH tolerances for acidity.
If only thoughts were as easy as reality …
Hi Philip,
You’re second thought was correct - it was rugosa X palustris. I didn’t keep banksia alive long enough to use it in any crosses, but would have loved to see a cross of it with rugosa. I never had even thought about the rootstock potential of rugosa X palustris but I’ll bet they would have had tolerated a wide range of soil conditions. I lost those F1 in a move but have seeds just harvested of palustris X Dart’s Dash which should be similar. I was shooting for a double-flowered version of those F1, which I hope to eventually use on bracteata to make double-flowered versions of the five [bracteata X (rugosa x palustris)] hybrids I currently have building back up from that same move.
Jadae, Rosa californica is one that I’ve always meant to get and try, but I didn’t know about the pH tolerance. That’s good to know.
“My guess is that it would have resulted in genetic breakdown as seedlings just like the canina/multiflora types did”
Could you give a little more information on these - in all the species intercrossing that I’ve tried, I haven’t tried canina with multiflora or derivatives.
Thanks, Tom
Hi Tom,
100% of my Canina x multiflora seedlings were awful. There were hundreds of them because they were easy to make and they germinated well. 100% of them were extremely small, spindly, mildewed from top to bottom and kind of zig-zaggy in shape. It was weird. I kept culling down to the most vigorous or least mildewed to see if any of them would grow out of it but it continued for two years so I tossed all of them. I could only think that it was a genetic issue. My only thought is that trying the cross in reverse order could be helpful OR using a multiflora hybrid like Bukavo or any of the other crazy Lens hybrids, lol. But I gave up because all I wanted was my own rootstock haha. All I wanted was a canina that didnt sucker 
The onle thing I liked about canina is that you could graft onto the stems at eye level. I liked this idea because I HATE bending over to do detailed work. It hurts. And, yeah, Ive heard of a greenhouse with benches =/
This is somewhat off topic, but I have a canina/rugosa hybrid that once provided the roots for my Snowpavement. It has simple small canina flowers, small rugose leaves with scented undersides when rubbed & oblong hips in the fall. The parent suckered under SP (now doing fine on its own roots) but this seedling doesn’t sucker at all. It’s been around for quite some time, but I have yet to figure out a breeding application. My focus is on plants that do well on their own roots, so I’m not interested in it as rootstock.
I have no idea why I even tried the idea. I really do not have anything to graft and I do not graft any of my own seedlings. I intentfully crowd my seeds to let those with superior vigor and root ability be known. I refuse to raise a rose that requires grafting (unless nematodes are in the scenario, obviously). Its also a good way to expose mildew prone seedlings in a usually mildew-free climate.
I am going to assume that the cross was an random ideal fantasy in my head. As in, “What would a good root stock in Oregon be?”
If one wanted to try Banksia x Canina they’d either have to freeze pollen or have someone in a southern state send them pollen of Canina when their Banksia was in bloom. This is one of the primary reasons I stopped using Banksia or Primula. My patience for the first wave of species bloomers became really thin, especially because they all had really fragile pollen to begin with.
To answer the question, I don’t think it’s a worthwhile commercial goal. Your own use is a different thing. For those odd emergencies when a cutting becomes budwood (thanks, Robert, for that heads up) or for a weak sister, I have my own rootstock. It’s a (probably selfed) seedling of one of those crazy Lens hybrids, Tapis Volant. I think of it as a super- Dr Huey without the prickles, red flowers, powdery mildew and blackspot. It’s thornless, vigorous, evergreen, roots easily, and looks like a rootstock, i.e, almost procumbent and vigorous. It’s one weakness is the possibility of the Ballerina crypto-virus…don’t know if it’s found in Europe.
Why use a rootstock for Hy Gigs, Teas and Chinas that root easily ? Budding is labor- intensive and will be abandoned in rose production here. My experience is that Teas budded on Dr Huey or Odorata are just as evergreen as the same own-root Teas. I don’t think the dormancy of the mild-climate rootstocks affects the dormancy of the semi-evergreen scion. It’s the other way around.
I have no experience with European rootstocks like canina or laxa used with the semi-evergreen classes.
Hey Lydia,
Your canina/rugosa hybrid… [with] simple small canina flowers, small rugose leaves with scented undersides when rubbed & oblong hips in the fall sounds to me like something with great potential.
Aside from use of the hips… I’d think it would have great potential as both a seed parent and pollen parent.
Two directions I would consider:
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Backcrossing rugosa pollen onto the F1 hybrid - or just planting huge populations of selfed seed. I’d be hoping for a repeat blooming type to sort out but still be strongly canina influenced.
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Using the pollen of the F1 on modern repeat bloomers, or maybe even the reverse cross… I would think hybrid offspring would be easily distinguishable and I’m betting that you’d at least occasionally see a few that would repeat. From what I’ve read, the Caninae meiosis usually breaks down as hybrid generations advance. ‘Carmenetta’ itself,which is glauca X rugosa, has been reported to produce pollen with widely varying ploidy (2n included). And also consider Dickson’s “Irish” repeat blooming hybrids that are reported to have come from Xhibernica (canina X spinosissima) crossed with Hybrid Tea.
I think you’ve got a sleeper sitting there, just begging to be used. “Put me in coach!” ;0)
Best wishes, Tom
Tom
I’ve grown out some seedlings, but they all seemed to be duplicates of the mother. No happy surprises there. At least its self fertile. The op seedlings survive winter unprotected in styrofoam cups. It blooms early so I’ll have to save the pollen for later crosses with my healthier floribundas and hope to get something short. It slipped my mind that its something I can use on R. roxburghii, or even Therese Bugnet.
I think the dude that invented that line of “hibernica” also included teas in his work. The work itself is a bit of mystery to follow. Its a rather unusual line of work but I appreciate the innovation for its time.
Oops, nevermind. I guess the “dude” that cross Canina hybrids with tea roses (and bourbons) was Geschwind. If so, I have a hard time believing that the lineage of the Irish series are 100% Hibernica x Hybrid Tea, especially since they look like they have Pernetiana in them. It feels as if the lineage is off by one generation somehow.