For those interested in species, I pinpointed a link to Walter Lewis’ monograph on the Subgenus Hesperhodos, which I show below. Lewis’ monograph, key and illustrations are terrific, nicely illustrating the inherent variability of species roses. When you combine this portion of Lewis’ monograph with an informative page published by the Arizona Game and Fish Department Plant Abstract on Rosa stellata subsp. abyssa A.Phillips, you have the full story (for now) on these two odd desert species of the subgenus Hesperhodos.
Here’s the link to the new Stellata subspecies abyssa found only on the rim of the Grand Canyon in Arizona:
Biodiversitylibrary.org has new beta software for downloading articles as .pdf’s from its outstanding collection of botanical references. Unfortunately, the page selection software is largely inoperable on a Mac. The following link is to a .pdf of Lewis work on Hesperhodos, as close as I can get. The pdf a very large file, so be patient while your browser downloads. The Mobot server is slooowwww, but my, oh my, what a service. This link is good for about a month.
I appreciated your talk in Palm Springs - sorry I didn’t get to meet you though!
R. minutifolia has interested me since the first time that I saw it at Mr. Ralph Moore’s nursery. I tried some crosses this year with it as pollen parent - all but one hip failed. I am worried that it may end up being a self pollinated hip that made it. We’ll see.
Thank you, Jim. The crowd was very polite, even though I could sense my topic wasn’t the fare they were accustomed to. I armed myself with plenty of images of pretty roses in self-defense.
Too bad R. minutifolia was disappointing. Did your plant go dormant by mid-June?
If R. stellata ssp. mirifica can survive a mild climate, it might be an interesting alternative. It is certainly more photogenic, based on the Texas shots. I worry that because its native range is somewhat high altitude (around 5000 feet), it may require a period of dormancy and/or a certain amount of chill to be happy.
I had R. Minutifolia for over a year now. Dormancy appears to be temperature based to me. When the temps go to 90 (which they do not get to here until August) it stops all activity and the leaves brown up, at which point I stopped watering it. It rained on it in October and it was amazing how fast it put out a new basal and fresh leaves and then began to bloom on the whole plant, and you could never have known how sad it had looked a month earlier by the time of the ARS conference last week.
My plant may have died… I had help watering my roses in the summer and I don’t think they paid attention to how wet the potting soil was… The plant looks dead, but maybe I can find some growth when I dig it up.
I don’t know if I killed mine or if it went summer dormant and I tossed it, thinking I had killed it. If I ever get my hands on another, I will immediately plant it on a sandy loam mound, with the hope that will give it perfect drainage. I had a one gallon dripper in the pot, but someone helped me out by swapping that out to a shrubler while I was on vacation. When I returned, it looked dead.
Well – dead looking is a good way to describe this plant when it is dormant. The canes do not stay green, but rather are gray. Jim, Cass, if you want another now, I made that offer on another thread here and so far I have two takers. Want to make that four? I’ll make a trip to that nursery after Thanksgiving to get mine and to get them for the others here that want them and then charge them each the $10 for the plant and the actual cost of shipping.
Thanks for the very generous offer, but I’d better decline. I think a plant will have a better chance of making it through our wet winter if I start it out during the summer drought, rather than during the winter. The average rainfall up here is on the order of 3 or 4 times what it gets in its native range, not to mention our wintertime lows of around 18℉. I read it takes Zone 8, but I’d like to see it with my own eyes.
Ok, I went to the Tree of Life nursery yesterday and now have the 3 R. Minutifolia plants requested and will send them tomorrow. Ann, I need your address. I have the addresses for Patrick and Jon.
I met Mike Evans there, owner of Tree of Life, who said it took him 15 years to learn how to propagate this rose from cuttings. The cuttings from which these three plants are propagated came from his mother plant which came originally from the Otay Mesa stand of R. Minutifolia in California. He also has a mother plant from the Baja stand, but had no plants available for sale from that one at the moment – but he says they’re the same. Anyway, we also had a discussion about Ralph Moore’s not particularly successful efforts with this rose, and he loves that someone is trying to do something with it again.
As for the difficulty in rooting this rose, he says he is convinced that this rose is allelopathic – i.e. its own leaves on the soil in which a cutting is stuck prevent root formation. What do you all think? Anyone ever hear of an allelopathic rose? (I haven’t.) He says one of the keys to propagating this one is to not have too many leaves on the cutting (or, I guess, to remove them from the area as soon as they fall off the stem).
There are certainly lots of examples of crops that inhibit germination of similar plants, including their own species. That is distinct from the tendency of plants to exhaust the soil of particular nutrients. But one of the classic examples of creosote bush in the desert may be an issue of water, not self-inhibition. Folks still argue about that one. I’d be surprised if a few leaves on the soil made the difference for a rose, more likely removing leaves stimulates some hormones associated with root growth and reduces the demand on the cutting aboveground. Of course it wouldn’t be that hard to test the idea by picking leaves from the mother plant and scattering or mixing them in soil. Maybe it’s hard to get enough similar cuttings to do a good dose-dependence study but it would be interesting to try.
Mel Hulse reported decent results rooting this rose by ground layering, with the layered cane pegged into the soil in a different pot. He grew it under a sun porch, which limited rainfall and maximized heat.
“The cuttings from which these three plants are propagated came from his mother plant which came originally from the Otay Mesa stand of R. Minutifolia in California. He also has a mother plant from the Baja stand, but had no plants available for sale from that one at the moment – but he says they’re the same.”
It’s a cute little rose. Prickly as all get out… So I was doing my homework and ran across this.
“the rose is known to be difficult to propagate from cuttings and only the species variation from Baja sets seed which are viable. The variety from Otay Mesa does not set seed.”
Hmmm that’s interesting. As I mentioned before, I just gave away my previous plant at the ARS National and got one with this batch to replace it. The one I gave away (which was purchased at the same time as Jim Sproul’s, did set hips. Tiny little things, but they were there. But I never opened one of them to see if seeds were in there. Jim?
The person who wrote that article, Ivy Bodin, is a friend of mine and is in my local rose society so I dropped him a line about where he got that particular piece of info about the Otay Mesa cultivar not setting seed. Here’s what he said:
So good to hear someone else is interested in Rosa minutifolia. A stunning little bramble from our very own area. As best I can remember when doing the article I probably got that bit of info about not setting seed from an article by a botanist in the Pacific Horticulture journal prior to my date of 1999. I also interviewed some native plant specialists especially from the Native Plant garden at Wild Animal Park where there is a stand of the rose. I also observed for myself and interviewed some staff members at the San Diego Natural History museum where specimens of the plant are catalogued from the 1800s.
I don’t know of anyone trying to breed with the rose and know nothing about the pollen. Experience is always the best teacher…they should just try it. I did talk with a rose species specialist Bill Grant in northern California about this time and he mentioned no success with growing the rose in his area. I have tried and killed about 3 plants here in my garden. I would love to get some more and give it a try again …trying to duplicate an environment. It seems they are quite in need of the lower San Diego area and down into Baja. A friend had a plant I gave him surviving planted in a raised planter in Carlsbad. I lost touch with him. And he mentioned observing the rose growing vigorously and blooming down the Baja peninsula. But I forget which season. That one sets seed. And a friend out in Poway had one growing out in their area, near Wild Animal Park. My plants survived nicely for about a year in their pots undisturbed and barely watered. When I planted them in the ground, they expired. The crucial time is the summer when they go dormant. Where are your breeder enthusiasts living? That locale will have everything to do with the survival of the plants. regards…Ivy
I didn’t get any seed set on it, but have one hip using it as the pollen parent. I have my doubts though that it is a true cross. Will find out soon! I think that my plant is dead… too much help watering in the summer time…