Hi everybody, I’ve been thinking of adding this old lady to my collection for a while and I would like to hear from you about it. What I think I could get from it are mainly medium tidy shrubs with cupped or rosette-shaped flowers, manly in the pink blend range, fairly fragrant blooms. My main concerns are about health and the ability to produce repeat blooming offspring, though.
I see that Austin used it in his early days, crossing it with Constance Spry to get Chaucer. Chaucer is repeat-flowering, which proves us that Duchesse de Montebello is indeed able to produce reblooming offspring, but its health ratings are quite poor (bad resistance to mildew and rust, average resistance to blackspot for what I’ve read); I also see that Paul Barden has used it to create two of his introductions, Allegra (x St. Swithun) and Marianne (x Abraham Darby) and in his writings he noted that it is capable of passing on good health and good bloom form fairly easily; both of his introductions are once flowering. I know he did not dislike once flowering hybrids, but I think that if getting reblooming offspring from it would have been easy, he would have preferred them and this makes me presume that, even if it is capable of it, it does not produce reblooming seedlings frequently. About health, my main problem is blackspot and I see that it is quite resistant to it (and its offspring too). Now, any of the three pollen parents used are known to be particularly disease resistant (Constance Spry has poor mildew resistance, Abraham Darby and St. Swithun require spraying to be blackspot free), and maybe by choosing a better pollen parent I could avoid disease-susceptibility.
If you have any experience with it, please let me know your impressions. Thanks!
If we assume MdB is triploid as reported and we assume it only has 1 copy of repeat. Ignoring any other genetic funny business it should be around a 1 in 6 repeat when with a modern tetraploid (and those 1 in 6 would be triploid as all tetraploids would have at least 1 copy of no-repeat)…which doesn’t sounds like terrible odds to get a rebloomer (~16.7 per 100 seedlings).
Beautiful seedlings, Rolf! I can see why that parent would be tempting to work with. (Not one I’m remotely familiar.)
I note that the Duchesse herself has reportedly higher ratings for disease-resistance than Constance Spry (for whatever that’s worth) on HMF, so I would hesitate to assume DdM is the weak link in the discontinued Chaucer. I wonder if repeat would have been the bigger headache for Austin.
How is resistance on your seedlings, Rolf? And if I’m not being too indiscreet, would you share what class of rose the other parents might be?
(Could someone point me in the direction of a clear-cut explanation of the math involved in determining odds of genetic outcomes for the more complicated, mixed ploidies? I know I’ve seen such before, and it made sense at the time, but I don’t recall how such stacked up. I need to bookmark so many things!)
Thank you all for your replies! Your seedlings are indeed very beautiful, Rolf. Your plants’ flowers look exactly like I would expect them to be. I don’t grow Astrid Grafin von Hardenberg myself, but I’ve heard some good things about it. If I may ask, out of how many seedlings did you select these ones? My main problem with once-flowering offspring is that the space I have available to grow seedlings is very limited and I couldn’t grow many of them. If a reasonable percentage of its seedlings have good looking/good scented flowers, I could think of narrowing them significantly even before they start flowering, based on vigour, health, foliage and other non-flower-related characteristics. Have you tested their fertility? Did you try other crosses that were not as successful as this one? How’s fragrance in your seedlings?
About the ability of producing reblooming offspring, I suspected it was something rare. Do we have proof of it being triploid? I mean, has it ever been tested or do we assume it is triploid since it is a hybrid china? It clearly has characteristics of both gallica and china roses, but it could be a gallica x hybrid china, as far as I know (please let me know if I’m wrong). If it is a tetraploid with three non-remontant alleles and one remontant one (AAAa), making it very unlikely to pass on reblooming genes.
Philip, I think that the “purely mathematic percentage” is obtained by assuming that 50% of the gametes are aploid whereas the other half is diploid (I’ll use A for non reblooming and a for reblooming, to keep it easier). The aploid half is 2/3 A, 1/3 a, whereas the diploid half is 2/3 Aa, 1/3 AA. Assuming it is crossed with a homozigous recessive reblooming variety, theoretically only the 1/6 of gametes that receive only “a” will result in remontant seedlings. I hope I hadn’t made it less clear than it was before
Easy visual (top and left are just all gene combos from each parent)
it ignores any genetic funny business (eg preferential pairing), there’s probably a lot of situations that skew it one way or another, but if all outcomes were equally as likely would expect something like the chart
It’s true, not once did I get a repeat blooming seedling from my ‘Duchesse de Montebello’. But to be fair, I never raised hundreds of seedlings because it never gave me hundreds of seeds.
It did make me wonder if I was using the same plant as Austin did. Given all the mislabeling of OGRs in commerce, it’s entirely possible that Austin and I have different plants under that name.
If I were to resume breeding (no plan to do so), I would definitely return to ‘Duchesse de Montebello’ to explore it more. It’s offspring were always surprisingly healthy for me, and bloom form was often superb.
I’ve wanted to try Allegra for years after growing Marianne (which makes a very large plant here, and while not free of black spot by any means, it’s better than average and keeps chugging along). Given how much less black spot-prone St. Swithun is here compared with the mostly perpetually-leafless Abraham Darby, it would be interesting to see if there are any parallel differences in the resistance of the offspring.
Thank you all for your inputs! Sorry for the late reply, but I have had so many things to do that it is hard to catch up with everything. Well I think I will had this lady to my “collection” next winter (funny how the roses I bought this season are about six or more weeks away from blooming for the fisrt time and I’m already planning what to buy next). I will probably play around a bit with her to know her better and then try something more specific.
I can already picture how a cross between the Duchess and some of the newer Austins would look like. Gaining chinensis rebloom is important for me, since my extremely limited space forces me to narrow down the number of seedlings in the first few months of their lives quite drastically, and I won’t probably cross her with other once-blooming varieties (even though I really like the idea of growing new OGR, maybe one day in a bigger garden I will). For the same reason I prefer fairly compact shrubs and, even though I think that a cross between Duchesse de Montebello and some bigger shrubs I have could result in something intersting, I will pass for now. My main ideas would be Emily Bronte, Roald Dahl, Vanessa Bell and Olivia Rose Austin, even though I have yet to try all of these in hybridizing.
What I would expect from these crosses would be fairly compact, healthy and shapely once-blooming shrubs, with flowers mostly in the pink range (with some luck I could get some apricots, but I’m completely fun with pink blooms) and, once more hopefully, some decent scent.
I’m also somehow intrigued by the idea of trying a cross with a semidouble form of R. multiflora nana perpetua. If I could get a semi-climber with fully double, blush-white blooms would be great, even if it is not the more likely combination! Being Duchesse de Montebello triploid, this could help getting some OGR genes down to the diploid level (would this be somehow useful, though?)
Please feel free to add any comment/suggestions/tips about this, thanks!
Please keep us updated on how things progress with results from these crosses: sounds very interesting. Of special interest is Duchess x Olivia Rose Asutin. I have gotten some goo things from Olivia’s pollen, and she is such a great plant. I have not one germination from the few seeds I have gotten from her (including extracting seeds). Perhaps that will change with age, but my experience so far says use her pollen.
If I can manage to get my hands on a plant of Duchess I will certainly be trying that cross. Another you might consider is Claire Austin (the newer white one), good seed parent. So perhaps you could attempt the cross both directions.
Have you had Emily Bronte set seed? Or Vanessa Bell?
Thank you Duane for sharing your experience with Olivia. Yes, I don’t think it is worth it trying hard to get a couple seedlings using as seed parent when it can used easily for pollen. I’ve done this before (planting hundreds of OP seeds to get just a couple weak seedling) with varieties I couldn’t get much pollen from, but I wouldn’t do it looks like much unnecessary work and space.
I will definitely keep you updated on this, but I won’t probably get much to say about this until 2025 or 2026, if I can get seedlings at the first try.
About Vanessa Bell and Emily Bronte, I’ve not tried yet crossing them with anyting, but I’ll keep you updated if I do
It seems to be a messy one, with some places seeming to be selling it at Small Maidens Blush (which is a different plant) eg
So it may be some people seeing a mislabeled plant and noticing the same foliage and assuming alba.
Either way, I don’t think there’s any conclusive evidence either way and the time period it was bred tends to have a lot of mystery/uncertainty, so probably won’t have any real answers one way or another unless someone does some sciencey things dna and such.