Friday, April 24, 2009

More work with Rugosas: 105-04-08

Seedling 105-04-08 is a cross of 'Sequoia Ruby' X "Magseed", the latter being a Ralph Moore rose I have mentioned before.

'Sequoia Ruby' is both a ridiculously easy and troublesome rose to breed with. It makes immense amounts of seed with almost any other parent, the seeds germinate at near 100% and a wide range of colors often result, including the occasional dove grey! However, this is often where the advantages end; 'Sequoia Ruby' has a lot of gravity and it takes a lot of work to escape that gravity. What do I mean by "gravity"? Well, it has the inclination to breed mostly miniatures that look a lot like itself, but in different colors. Most seedlings are upright growers to between 15" and 36", blooming with clusters of loosely HT style blooms that open to double cups of 40 or more petals. The foliage almost always looks the same as well: miniature and semi-matte, in medium green. However....

Occasionally you get lucky. Case in point is this cross. Apparently "Magseed" has a lot of gravity of its own, because I got a number of seedlings that were clearly Rugosa influenced shrubs that grew quite tall and had 3.5" - 4.5" blooms. 105-04-08 is what I consider to be the best of the lot and it just gets better every year. It is fully fertile in both directions (I am using it in breeding extensively this year) and is easy to propagate from cuttings. It has also grown out in the test bed for four years now and is one of very few roses that is almost 100% resistant to Blackspot. Sounds good so far. Criticisms? Well, It is a bit upright and lacking branching as much as I'd like to see, so it takes a while to fill out as a shrub. (Based on the single original plant in the test garden. The large one in a pot in the breeding greenhouse is a lot fuller and shapely for some reason) It isn't quite as generous with bloom as I'd like it to be, but I hope to correct that in a next generation. Neither does it have much scent, but the color....WOW! No photograph shows how rich and velvety the petals really are. Its a magnificent color, starting out a deep garnet red and aging with violet-purple overlay on the outer petals. I expect to cross it back to some of the "purebred" Rugosas to see if the shrub habit can be improved, and maybe cross it with some Hybrid Musks to increase the volume of bloom. 'Trier' is capable of some serious magic so maybe I'll try that.


  1. Does the red turn purple and burn in the heat?

  2. It turns more purple but more along the crimson/beetroot line. It does not burn in hot sunlight, no!

  3. Beautiful rose Paul!

    With the idea of melding the carefree nature of rugosas with desireable traits from other rose types, I recently ordered (and received) Polareis and Wassagaming from Suzy Verrier.

    I have heard in the past and been reminded again that crossing rugosa (deciduous) with other roses considered evergreen (in some climates) can result in real problems with disease. What is your take on that? Disease is the very problem I would like to avoid by using rugosa in hybridizing....


  4. Rob,
    Correct, breeding Rugosa + Modern can lead you into all kinds of problems, not the least of which is foliage disease. I think its a matter of careful selection to find cultivars that escape these problems and move forward with these. Fortunately "Magseed" is one such selection. It doesn't have perfect disease resistance, but its far better than many first generation Rugosa hybrids. Maqny first generation Rugosa hybrids not only Blackspot and Mildew badly, but some also Rust so badly that the foliage is orange from Spring to Fall. 'Rose a Parfum de l'Hay' in particular comes to mind: I dug it out and tossed it years ago for this reason. 'Vanguard' Rusts badly for me as well, and gets Blackspot rather easily. These are things to be avoided when working with Rugosas, and as I say, the only thing you can do is cull plants that have these problems. It CAN be done: think of 'Linda Campbell' and some of the Explorer series, which rely on Rugosa in their pedigree.

  5. Thanks Paul. So it sounds like if I am willing to be rigorous in culling that the risks are worth the possibilities.... My primary goal isn't cold hardiness (though that would be nice)--but I am specially interested in developing hybrids that are as carefree as rugosas but with improved volume of bloom, flower form, etc. Sounds like it could be an interesting journey :)

  6. Excellent things are certainly possible, absolutely. Unfortunately one of the Rugosa traits that likes to resurface in its hybrids, sometimes even three generations away is the sparse rebloom after the first flush. An otherwise excellent rose can be disappointingly stingy with bloom after the June display. But progress can be made and its worth pursuing. Fortunately L83 is very good about repeating after the first flush, and it appears to pass that on.