Rifis,

Where does the ADR designation so many Kordes roses have won fit into this disease rating system?

An ADR winning rose is not specifically rated on degrees of disease resistance. Neither does an ADR win specify how resistant the rose is to black spot or powdery mildew on an individual disease basis. I assume these two diseases are lumped together under ADR.

Personally, a very black spot resistant rose is a more desirable characteristic than equivalent powdery mildew resistance, since the all summer long black spot threat is far more serious here than minor spring/fall powdery mildew outbreaks. In drier climates where powdery mildew is far more serious an issue than black spot is, knowing just how resistance rose is to PM is far more important than knowing its black spot resistance.

I also think an independent, hopefully impartial group doing the evaluation, such as is set up under the ADR system, carries more credibility than a rose breeder or marketing concern pronouncing disease resistance statements on their own roses.

Moses

I agree with Moses that mildew is a bigger problem than BS. Mildew will totally burn the rose leaves and stop them doing their job. BS can be kept under control with a spray. By the time you use a spray on mildew ( which is often hard to see) the severe damage is done. I would prefer separate ratings for my PNW gardens.

The unfortunate matter is that cercospora leaf spot is becoming very wide spread and has added an additional disease burden above that of black spot and mildew.

All in all, I like to hear about a rose's disease rating no matter who does it, even if the credibility of the proclaimer or of the disease information is in doubt. It's when no mention at all about a rose's disease resistance is made that makes me question why, and look further into that rose's credentials.

Moses

It IS a shame that they have combined the two because different areas seem to suffer from one, but rarely the other. I'm into the more information, the better camp. BTW, Fire Opal is an incredibly healthy rose that makes it difficult to accept less in all my others. :(. She was one of my first last year and set the bar high!

Moses:

Your question and observations about ADR piqued my curiosity. I went to the ADR site, English translation, and looked at the "Scheme of Evaluation".

Apparently, over 3 years, at multiple growing sites, contestants are rated on winter hardiness, vigor, bud/flower form, "blooming and duration", color from beginning to end of blooming, fragrance and self-cleaning. And, in addition, "resistance against leaf diseases" - which, I calculate, counts for roughly 38% of the final score. And, finally, "general impression of presentation" (otherwise not defined at the ADR site) which counts for a whopping 25% of final score by my calculation.

I'm surprised both by this high weight given to the last criteria, and well as by the leaf disease resistance criteria carrying a weight of only 38% (I had imagined it was much higher).

I imagine the ADR scoresheets for Kordes roses are made available to Kordes Rosen, and that they use them in generating their own ratings.

I agree with your observation about the desirability of an impartial independent group in generating ratings. Having said that: keep in mind that the ADR site points out "...ADR testing was established by Wilhelm Kordes 50 years ago".

But more to the point: I've seen comments from members on the Rose Hybridizer Assoc. forum stating things like 'the only (or, at least, the MOST) trustworthy/ non-inflated disease resistance ratings come from Kordes'. My own limited experience is that Kordes'/Newflora's ratings for BS have not been inflated - if anything, some of their roses have BS resistance superior to that suggested by their ratings. An example in my garden is Brilliant Veranda: +++BS rating, but ++++ BS performance. I do realize that resistance is "local", and others' experiences may vary.

I, too, would like to know how much Star/kordes.us factors mildew resistance into their "mono" disease resistance rating - was it really necessary for them to drag Kordes down to the same level they maintain for the rest of their Willow Grove empire? Is Germany no longer boss in this matter?

I prefer the older style of ratings since black spot is the main issue here. I think the New flora ratings were very accurate.

Agreed. As to the scoring, it really isn't anything new, it is just a lamer system since the combined health scores are used. While I would not be surprised if this were a copy writer's error (excellent, exceptional... Whatever...) it appears the 8 stars (combined scores for BS and mildew) earns the "exceptional" rating. There are a number of roses on the Kordes.us site that do not have *any* "rating" included, one or two of which might theoretically earn the "exceptional" assuming that references an 8-star BS + mildew rating.

I definitely miss the NewFlora system, adapted from Kordes in Germany. I also note that some of NewFlora's offerings don't appear to be on the new Kordes.us site, so they may be reducing the number of offerings. That would be very unfortunate as the Kordes line brought a lot of very healthy roses into our market.

Does anyone know if Chris, formerly of Newflora, is still involved with the evaluations and distribution of Kordes.us? Does she still frequent this forum?

Does anyone know why Fire Opal has been discontinued?

I don’t know. I do see that it is missing at the local website.

Possibilities include concern that it was putting other offerings in the Kordes catalogue to shame. Or that Star hired the Houzz webmaster to take over the kordesus account.

Interestingly, I am expecting a FO to arrive here by UPS next spring. After it clears customs up north.

Fire Opal has not been a very good performer here for me. Although Lilyfinch had better luck with her when she lived in the area. Her she is middle of October which is not a good time for us concerning BS but this is not unusual:

I have two. And they are both some of my best performers for both Bloom and disease resistance. I do nothing for them so that's a testament to their hardness in my area. I rarely see spotting on the leaves.

Fire Opal is seriously the bomb here! No disease, blooms all the time, even through the summer heat and humidity. Has a gorgeous girly -frilly look but is tough as nails. I call her my dupe for Belle Story. FL is black spot hell and as everyone prob knows by now, I never spray.

I got 3 Fire Opals on clearance a few yrs ago at Walmart for $3 and change each. I didnt expect much and might not have tried them otherwise. Some of the best rose cash I've spent to date :D

I have all 3 in the ground not sure if they are grafted or not but I suspect not.

Mine our own route from Chamblee.

^^^

Speaking of ”route” and “Chamblee”:

Chamblee’s is now located in Winona

(Don't forget Winona
Kingman, Barstow, San Bernandino)

though it’s Winona TX. Not Winona AZ (the one Nat mentioned).

My experience is that many roses that are BS resistant here are instead prone to cercospora spot — Which folks might mistake for blackspot.

(It looks to me that upper left leaf in subk3’s photo above has that hallmark gray center in the middle “shot hole“ look of cercospora infection...)

While a rose infected with Blackspot typically drops leaves (entire bush may defoliate!) with Cercospora the leaves will often just hang on looking cruddy.