Montreal Botanic Garden Diease survey

Certain roses on HMF like William Baffin say In September 1998, the Montreal Botanical Garden (Le Jardin Botanique de Montreal) carried out a survey of its roses’ resistance to black spot, powdery mildew and rust. This is one of the outstanding varieties which showed a 0% to 5% infection rate. The data was taken on well-established roses.

Does anyone have the full list or know where to find this survey?

MBG has a list of recommended rose varieties. Curiously, it does not include Wm Baffin. I don’t know that this list (see link below) has any relation to that disease survey. From the sorts of error in it, I suspect that it does not.



William Baffin is definately a great rose, however, it does have race specific black spot resistance and in the upper Midwest it is falling apart when that race is present. I am going to be presenting a paper on infection of the roses in the Earth-Kind trials in a few weeks at the American Society for Horticultural Science meetings and WB is part of it. Selecting for strong horizontal resistance and making conditions condusive for black spot and bringing in multiple races like Bill Radler did was very successful. Fortunately, the race that overtakes WB does not seem very widespread yet.



I saw that web site last night Peter. I think you are right because of some of the roses in the list. The list also does not contain a few more roses I found when I was searching for a list. I want to compare what they have with list from other regions to see if their are some good choices for possible parents for disease resistance.

David I am sorry to hear that William Baffin has only race specific black spot resistance. I do not like the idea of making a single lock and key resistance. I want to make a safe or a plant that gets black spot but lives well with it.

That being said I used both William Baffin and Baby Love in crosses this year. But I used Baby Love for it mildew resistance, plant form and repeat bloom. I considered it non resistant to black spot because of the single resistance. I used it mostly for the plant form and mildew resistance. I was thinking William Baffin had more than a race specific resistance. I guess the good seedlings from it I will consider as non resistant for my purposes.

David do you know any other plants that have race specific resistance. I know a few like Tropicana which when it came out was suppose to be a marvel in disease resistance but crashed as black spot gained the keys to its front door. Do you also know any which have non race specific resistance; I am hoping Goldbusch, Iceberg, and Applejack are on that list because I am working with them now. I plan on getting Carefree Beauty this next year do you know about this one.

Sorry for all my questions? I am trying to use roses that have resistance to black spot early on in my program.

In my experience Colette has race specific resistance, as well as Morning Has Broken. Iceberg is always a BS magnet here, don’t know if it has any resistance at all. Never saw healthy one unless it is sprayed religiously.


I have never seen a perfectly healthy Iceberg but I figure it has some resistance in their because every where I have seen it where it does get black spot it seems to tolerate the disease instead of dieing. The fairy seems to do the same thing. I could be totally wrong how ever. I was not into roses back then so I sometimes did not pay attention to things that would have helped me now.

Hell back then I could not figure out why people even grew roses? I would see these hybrid teas struggle for their life. First it would rain for three or four months straight and they would defoliate from black spot and then the rain would end and drought would make them wilt. Plus I would receive these pictures from my sisters of Japanese beetles on top of this. Finally I never did like the look of them in the garden. They look to me as a little ungainly. The rose that I was most familiar with besides for hybrid teas was David Austins and they seem to do all right, but they suffered from disease and they did not like winter much.

Hi Adam,

Great question about which roses have stronger horizontal resistance. Vance in his Ph.D. found ‘Applejack’ to have high partial resistance. ‘Carefree Beauty’ and ‘The Fairy’ do too as do ‘New Dawn’ and ‘Seafoam’. They get black spot, but it progresses slower than others and when the weather is good it is severely limited. That is why they probably have risen to become staples planted over the decades because they generally perform well. With these roses it is important to know that as we cross them with more susceptible parents we tend to reduce the overall horizontal resistance. Since it is primarily multigenic in control, we get a wide distribution for degree of partial resistance among offspring and can find individuals towards the resistant end.

Bill Rader was very very successful in generation after generation building horizontal resistance. He likely had diverse black spot races because of introducing black spot and encouraging an environment conducive to black spot. His work is a great example of successful recurrent selection for horizontal black spot resistance. There is some race specific resistance among his roses, but there is high partial resistance when that is overcome generally.


I was planning to use Applejack, Goldbusch, and Carefree Beauty next year so that is good to hear. I figure Goldbusch is in this list because it has the same genes as applejack. Both applejack and goldbusch I received as band plants this year. Carefree Beauty I am planning to get to replace at least one of the plants that I will discontinue to use after this year.

I was planning to use the Fairy this year but the dry winter weather got to it. I am assuming the resistance for the fairy, new dawn and sea foam primarily comes from R. wichurana. Of these three plant coming out of R. wichurana which one is the better parent in your opion? Would it be worth it maybe to go all the way back to the species? I got an idea about crossing R. wichurana and crossing it with a few of the native american species and going from their.

Oh one more question has anybody used Lady Gay? If so how well does it work?


Regarding the use of ‘The Fairy’, ‘New Dawn’ and ‘Sea Foam’ in a breeding program, I would first define the objective you have to help you make your choice. For example, do you want a shrub, groundcover or climbing rose? ‘The Fairy’ and ‘Sea Foam’ are more conducive for developing the first two types, whereas ‘New Dawn’ is excellent for developing the latter type.

“Would it be worth it maybe to go back to the species?” Absolutely! Especially to develop new types of roses. In the case of Rosa wichurana, if you are thinking of working, for example, with the native Rosa woodsii (2n), I would be inclined to first develop a species hybrid at the diploid level and then work with Rosa wichurana (diploid). Example, Rosa rugosa x R. woodsii. You should be aware that such hybrids may already exist (‘Carlos Dawn’, ‘Lac La Nonne’).

I can’t emphasize enough the importance of using Rosa wichurana in a breeding program for developing disease resistance, and it is good to see you on this path.