New bourbons?

General Discussion
1

Hey all,

I am completely new to rose breeding, but I’d love for people to humour me on what is more of a thought experiment than a plan. I’m curious about the possibility of the breeding of modern Bourbons by going back to the original crosses.
As I understand it the first Bourbons are purported to be damascena x chinensis, possibly Quatre Saisons x Old Blush. I have also seen it stated that a chinensis x centifolia origin may be more likely. And of course it’s vey possible both parentages existed under the vague category of “Bourbon” before dropping into relative obscurity.

My ponderance is of the possibility of once again crossing damasks and chinas, and whether such roses have been recently created already and I simply haven’t seen them. I’ve seen it written in a pilot study somewhere on creating modern perpetual damasks, that using HT hybridisation to achieve something like this is highly difficult because perfume companies largely hate the underlying tea scent found when you distill Old Rose-scented HTs. (Aside, is this true? Are widely-praised scents such as that of the in-commerce ‘Francis Dubreuil’ HT truly still in possession of a tiny bit of tea undertone?)

This is what sparked my curiosity for using only the genetics of gallica, moschata, fedtschenkoana, and adding chinensis. Specifically, using ‘Kazanlik’ as the seed parent and ‘Cramoisi Supérieur’ as pollen. In the most ideal of circumstances, this could potentially lead to only a modest reduction in oil content, the addition of a pleasant raspberry undertone to the damask scent, disease resistance, and near-year-round flowering in a warm climate.

Now, mama didn’t raise no fool. I know that the chances of retaining all of those positive traits crossing these two roses is literally one in a million. While I’m not a botanist nor a rose breeder, I am a scientist, and I understand the chaos that tetraploidy (not to mention CS’s triploidy) can bring, I am under the impression that Kazanlik, despite being older than Christ, is still an F2 hybrid due to millennia of clonal propagation, so I also know that throwback there would be huge.
However, I have read that some people on here have had some success in the beginning steps of artificial speciation of damasks just for the novelty of it, though such a project has had no reason to be taken through to full stabilisation.

And so, I arrive at the totality of my question: Assuming I desire to breed a modern Bourbon rose for industry (rather than garden) purposes with high oil content, a scent profile very close to R. damascena, strong health, and profuse continous blooming; and assuming I had many years of time on my hands and a small hobby farm at my disposal (which I sadly do not); do people think it would be a theoretically fruitful endeavour to:
a) breed Kazanlik, and possibly other damask roses together into a consistent, stable artificial species that ceases to throw back
b) cross this new rose with Cramoisi Supérieur’ or another scented China
c) eventually succeed in producing a rose that now had all of the traits I listed
d) possibly doing step (a) to Cramoisi Supérieur’ to potentially add the potential of heterosis in the now F1-like crosses

Thank you all for reading and hopefully humouring me in this, and if anyone does have several decades to kill and a small farm at their disposal, please feel completely free give this absolutely bonkers idea a go! For now, myself, I’m going to start with some extremely unscientific crossing of random roses I have just for the sheer enjoyment of seeing what happens! But I enjoy learning about what is scientifically possible so would love to hear the thoughts of those more knowledgeable and vastly more experienced than I :slight_smile:

2

There are many points in this that could be discussed at length, but starting with the basic premise, is there a market for the rose that you propose to create? Bourbons and other repeat-blooming roses with intense fragrance have been used to a limited extent for distillation, but they have never really competed well commercially with pure Damask roses for oil and attar production. One of the most important considerations is that once-blooming behavior is actually a major advantage for a crop with such a high labor cost; having to pick blossoms repeatedly or continually over a long season requires vastly higher labor input, and there are significantly lower yields per harvest; blooms produced during hotter months will also be fewer, smaller (and often with fewer petals), and will probably produce reduced fragrance. Since there isn’t a major market for (less healthy) existing Bourbon roses that already rebloom, and which could already be employed for production in regions where disease isn’t a significant problem and labor is sufficiently inexpensive, would producing a healthier substitute really gain you anything?

Another critical point is that you aren’t especially likely to advance disease resistance much (if at all) by starting out with ‘Cramoisi Superieur’ (or most other Chinas, really). ‘Cramoisi Superieur’ is an outright blackspot magnet here, and it probably gets by photosynthesizing as much with its canes as it does with any remaining foliage. Most fragrant Chinas are still fairly susceptible to blackspot where the disease is prevalent, and those few Chinas that are particularly healthy generally seem have a higher complement of tea rose in their backgrounds. Even if you used one of those, or opted for a very healthy tea (many of that class are also susceptible), it’s unclear that their health could or would overcome the inherent disease susceptibility of the Damask parent. None of the pure, original Damask roses are resistant to blackspot, either, so it’s unclear whether you could obtain sufficiently healthy offspring by regenerating further Damask roses from ‘Kazanlik’ and its ilk, or even by going back to the parent species and starting from scratch. There are maybe a precious few Damask or Damask-adjacent hybrids that are healthier than ‘Kazanlik’, like ‘Ispahan’ (which is probably not a pure Damask, but its precise background is not known), but they may or may not be fertile or necessarily produce healthier offspring. While it’s possible that more careful selection along the way during the whole process would yield improvements, there are absolutely no guarantees that you would succeed. You would have to go into it with a very open mind and a willingness to experiment and fail.

Overall, it may be worth a try depending on your goals, but it is not clear that the desired breeding outcome could be met or that there would be a significant commercial oil/attar market for the resulting hybrid.

Stefan

3

I think that PhenoGeno roses, in Serbia, is working to produce more varieties for rose essence production. I can’t find anything specific on their website at the moment, but I recall seeing something about this on their instagram page. I can’t remember if their goal was to mantain Kazanlik’s essence type or if they wanted something novel. They use modern breeding technologies and marker-assisted selection, so their job could be easier than trying to do so in our backyards

4

I like the idea or re-doing old crosses, especially with some differences in parents. It may be possible to avoid some of the old pitfalls. On the other hand, getting too far from the original can lead to some losses. For example, crossing a China/Tea of whatever origin with ‘Kazanlik’ would probably give a once-blooming Hybrid China. But a Monthly Damask has its own mode of rebloom. Balanced with the Chinese Everbloom allows a little more flexability.

For example, Reine Victoria combines Bourbon with Noisette, and its behavior can be modified. When cut back to the ground (nearly) a strong plant will push up canes with large flowers like a Hybrid Perpetual. But allowed to grow with some support as a pillar, the flowers become smaller, in larger clusters.

The original Bourbon rose was a bit of a mess that needed a firm hand to bloom well and thrive. Much of this has to do with the great differences in the growth and blooming habits of the parents.

China Roses, generally, are repressed climbers. Remove the “everbloom gene”, and the plants will revert to their ancestral growth pattern. Remove the terminal bud, and the two or three buds below the cut will break and resume the upward climb.

To the contrary, the “Autumn Damask” that was growing on the island at the time generally bloomed twice each year when properly managed. It was not a climber. When this growth habit was combined with the “everbloom gene”, the result was a plant that “bloomed itself short”, so to speak. They sent out too many twiggy shoots, bloom size declined … a mess.

In addition, the hybrid made so many buds in each cluster that the blooms were badly formed, or the buds dropped. This was worse in cooler weather, when even more buds form, refused to open at all, and turned black.

I do have a report from a gardener in northern India who got this variety to bloom well and thrive.
An Expert: Rose Edouard (1885)
http://bulbnrose.x10.mx/Roses/breeding/ExpertEdouard1885.html

One more note: Not all Bourbons were remarkably fragrant.

If I were doing this, I’d start with some of the old Teas and their kin, particularly those with only one flower per stem, or just a few. I’m thinking Isabella Sprunt/Safrano, Devoniensis, Duchesse de Brabant, and Comtesse du Cayla for more lively color.

And if you want to get Noisette “blood” in the mix, I’m partial to Lamarque, William Allen Richardson and Reve d’Or.

Souv. de la Malmaison is about as good as the Bourbons can be, especially the climber. Pity that it is not more fertile.

5

There is an institute in Bulgary that has been breeding new and better varieties for oil extraction. I saw some of these roses in Coloma, Belgium. I haven’t smelled that strong a scent in any modern rose I think. One variety was called Iskra. Tried to contact the scientists that created that one, but hadn’t had any luck there. That was in 2018.

Institute in Kazanlak, Bulgaria: “Institute for roses, aromatic and medicinal cultures” - Институт по розата и етеричномаслените култури - Казанлък

I’ve tried a few crossings with Ispahan. Never saw one hip on that bush. This year I’m also leaving all flowers until autumn just to confirm my strong suspicion that Ispahan is in fact not fertile. A shame, because it is one of the finest Damasks out there.

6

I also tried pollinating ‘Ispahan’ with copious fertile pollen last year, and although I saw some promising swelling, the hips aborted fairly early (that’s actually why I made that comment about possible infertility!). It might not be workable as a seed parent. If I were to try it again, I would probably hunt for anthers in the hopes of finding useful pollen. It is in a class by itself, and seems worth the trouble.