Repeat in First Generation Species Hybrids

I was under the impression that a cross of a once blooming species with a repeat blooming rose always resulted in a once blooming hybrid?

I’ve got more than one example this season of repeat flowering hybrids coming out of a repeat blooming seed parent crossed with a once blooming species pollen parent.

I’m almost 100% certain these are crosses and not the result of open pollinations.

I have a friend who got a repeat blooming hybrid out of a similar first generation R. helenae cross.

Any thoughts?

Thanks, Robert

Maybe R. helenae isn’t either what you thought it was… or maybe–

You were very lucky.

For years, as Enrique my thoughts about the many recurent species F1 hybrids encountered was to think the “species” was not true. But it is repeating continuously and with species that are so unique one cannot doubt.

Recurence is a curious phenomenon with different expression at different localities. I.e. the recurence of banksias in part of California when none is observed here french Riviera with a very similar climate. When it never does at some other places, here bracteata consistently repeats at end of long shoots.

Actually I am thinking that once blooming is an adaptation to the species original conditions. This adaptation being eventualy lost at another location or eventualy annulated when mixed in an hybrid.

Then for me recurence is loss of adaptative once blooming as long as a better hypothesis is found.

In the past, a lot of synstylae once-blooming species crossed with repeaters have resulted in roses with a high capacity with blooming. So, I am guessing that since roses are not like your typical plant hybrids in respect to predicting outcomes (there is a name for this, but I forgot it…I think it started with poly) there may not be anything specific at all on a genetic level that controls repeat blooming. All that I really know is that it is related to growth hormone levels and timing.

Here is an interesting chart though:

Notice how a few of the OGRs outrank many of the HTs? Granted, they are older HTs and newer HTS are often more well-branched, but it is still amazing!

Here is a list of my recurrent first generation species hybrids from last season.

Riverbanks x R. xanthina

Riverbanks x R. alabukensis

Lyn Griffith x (R. glauca x R. pendulina)

Lyn Griffith x R. xanthina

Lilac Charm x R. Webbiana ‘nanothamnus’

Audrey’s Rose x R. palustris scandens

Wow. Interesting.

So theyre all over the section map, and briars instead of ramblers that lost their “ramble”.

So this makes them most similar to roses like Stanwell Perpetual and Golden Wings. I do remember a Rosa pimp selection that was a repeater. I think it was a small groundcover type. I dont remember the name. And then there are the Boursalt’s similar to your Lyn Griffith x (R. glauca x R. pendulina). The only superficial link I can think of, other than the above, is that theyre mostly species adapted to places with severe climates.

I think there must be some connection with the repeat characteristic being present in the seed parent.

My friends repeat blooming hybrid was a cross of r. helenae x R. rouletti so this isn’t always the case.

Whatever the reason it certainly changes the way I think about species crosses.

It seems we could be doing much more in terms of species exploration.

I agree. Ive been crossing them like mad this spring. I even made some that have probably been done before like Rosa chinensis sanguinea x Rosa rugosa alba to some like yours such as Rosa chinensis sanguinea x Rosa primula. I need to find someone local with land that will test for me, lol. The problem is, I completely lack trust in anyone not like us regarding the care of things that may only happen once. I’d fear a reply like,“Well, I had the weekend off so we went to the beach, and it was hot out and it died…sorry!”

I don’t trust anyone. Everything is irrigated automatically.

Robert

You wrote:“It seems we could be doing much more in terms of species exploration.”

I could not agree more!

Breeders that are where growing roses has limits know that if trying at improving the crossing of regular CVs is practically hopeless.

Allmost all better for desease/frost resistance roses are from species crosses.

Ralph Moore did a lot of species crosses when he was not so young and got outstanding results from them.

I very much agree that there is a tremendous untapped potential in the species.

And as for repeat in the first generation of once-blooming species with a repeat-blooming… I’ve seen all kinds of unexpected results in this area.

I wouldn’t totally discount the general idea, but characterize it as only a generality.

I have a multiflora X rugosa seedling that faithfully reblooms at the tips of the new canes. Like Pierre and Enrique, my first assumption was to be suspicious of the “impure” nature of the species (multiflora) that I used. It had extra petals and so could have had some mixed ancestry. But I’ve also seen too many other oddities to keep thinking along these lines.

I’ve had repeat from Rosa carolina X rugosa, whereas Rosa arkansana X rugosa gave no rebloom for someone else. Rosa carolina and Rosa arkansana are similar North American tetraploids that both have a tendency to repeat.

And that same Rosa carolina crossed with ‘Fragrant Cloud’ gives no repeat.

By the way, that same “impure” multiflora gave me no rebloomers in crosses with Rosa chinensis ‘Mutabilis’.

So, as I mentioned above – only generally, once-blooming X repeating will give once-bloomers. You never really know what to expect when you’re working with species crosses. There are lots of surprises!

I’ve always been curious about species exploration but figured it would take repeated generations to get repeat and some of the other attributes we look for.

I probably won’t be bringing too many more species into the mix at this point as it will take years to explore the possibilities in these.

I have a feeling some of this is luck as I did get a large number of once bloomers out of some crosses including those between repeat blooming cultivars.

I would be curious as to how recurrent some of the F1 species truly are – or do they rather demonstrate occasional remontancy? Pre-chinas, and without use of the rugosas, many “may-rebloom-in-fall” roses existed. Consider the autumn damasks and hybrid perpetuals. Many F1 hybrids can generate some rebloom later in season but continuous bloom?

I’m curious as to how much potential parents of such “occasional rebloom” near-species roses have to create continuous bloom in subsequent generations. R. fedtshenkoana, for instance, is credited with giving the Autumn Damasks their remontancy, but continous blooms when used with other roses? I dunno…

Thoughts? Experiences?

As I wrote earlier when all banksias are once blooming here (even Purezza never rebloomed) allmost all seedlings I got from Chinas x single flower banksiae are recurent. Not occasional or late. Most are consistent and early rebloomers. Just like earlier polyanthas.

Purezza has rebloomed for me, Pierre. Lightly, but it has rebloomed for me.

I have a single OP hip of this rose which is still stratifying. I hope that it can germinate.

Pierre, I would be very curious to see some images of your china/banksia plants.

-Philip