This is my third season in New York. The first summer there was very little BS. Last year summer was wet, and I saw some BS, but did not loose any plants to it. Suzanne Verrier wrote a small pamphlet about growing roses organically in Maine. It is available from Lehman's for around $3. She said in it that she simply puts up with some BS. I so far have not wanted to spray; I have small grandchildren, and small children live next door.

Organic sprays are generally considered more trouble than they are worth. They aren't that effective, and require a lot of reapplications. People who don't want to spray can grow reasonably blackspot free roses by careful variety selection.

Hi Jerome! No one that I know has been able to use organic fungicides successfully over any extended period of time. A couple were able to use sulfur over a single season, but found it wasn't effective in subsequent years. they also require frequent application.

When any one tells me that they don't want to use "chemicals", I recommend that they skip the hybrid teas and stick to blackspot resistant varieties.

I tried to use everything organic available - baking soda and its derivatives, copper, sulfur, rosa flora, neem, Serenade etc. Sulfur is more effective than other organic sprays, but it offers only moderate protection with tremendous amount of work. You have to spray after every rain, which can be several times per week. You can't spray in summer when it is 90ies and this means almost all summer. So roses will defoliate in summer anyway. It is not effective for big roses where you can't provide complete coverage, etc. Some roses get burned by sulfur, no matter what. I used it for several years. Never again. So in my experience organic methods don't work here. The only solution if you don't want to spray Bayer or Banner, etc is to choose resistant roses. To me it means oncebloomers and less than a handful of repeate blooming ones (Knock Out, Quadra, Darlow's Enigma)
Olga

Thanks for these great responses. This is helpful. Dang! The plants I love best are disease prone. Olga I hope you still have your gorgeous Abe Darby!

Hi Jerome, my roses get blackspot and drop their leaves in summertime, however this does not diminish vigor or blooming.

I think roses grown without fungicides gain natural strengths so that they can thrive, even with blackspot present in the garden.

I grow a wide variety of roses in my no-spray garden; I think that organic topdressing and fertilizers help the roses to thrive.

What does it mean thrive? Does a bush without leaves "thrive"? Roses are not flowers on canes.
We all wish to believe in organic, chemical free gardens but reality is reality.
We should also not forget that most roses we love are not exactly indigenous to the east coast. There are indeed native plants, highly resistant to BS, but that's a different looking garden.

So many roses I adore are too blackspot-prone for my no-spray garden, so I go visit them every year in public gardens and leave it at that!
I totally agree with Krista-- organic feeding, topdressing, good mulch and faithfully watering is the ticket. I also treat my roses to cold showers to refresh them and to discourage spider mites and aphids.
I have found virtually NO modern hybrid teas or floribundas with enough BS resistance for my garden. So I choose from shrub roses old and new-- from Griffith Bucks to Kordes Fairy Tales. I also am growing lots of antiques which like our intense heat-- teas, chinas, noisettes.
Anyway, my days with a respirator and Tyvek suit are over! I want to live to a ripe old age with my roses.

No. Not the blackspot prone ones anyway.

Mine's not fungus-free, no! But I do grow some floribundas and even a few HTs, and they shrug off BS (at least with age). I haven't seen a defoliated one in ages. I see spots here and there, for sure, though.

I do spray them with Bayer in really bad springs or when they are quite small, so I'm not an organic gardener.

And I do spray them with strong water in the summer heat, in case that makes any difference. Believe me, it dries before nightfall :) Maybe it helps against fungus? I just know that they like it, lol.

The leaf drop is not permanent, roses grow new leaves. Rejuvenation is part of their natural cycle.

Krista, here most BS prone roses don't have leaves from June on. New leaves get BS right away. They are naked all summer. These roses definitely decline and in some cases even don't survive winter. When I gardened in colder zone(3), it was all different story.
Olga

I grew modern roses, mostly hybrid teas, in a very bad blackspot area for about ten years using only sulfur (micronized elemental sulfur). By late season the roses would have lost the lower 20-30% of leaves but looked pretty good. A few of the most susceptible varieties (Sexy Rexy, Angel Face, Ivory Fashion) were worse and didn't look good by midsummer, but they could be grown under that regimen.

To get this result, it helped to prune severely, and it was necessary to start spraying early and rarely miss a week. I found sulfur to be almost as effective as the Ortho triforine spray I had used previously. But tebuconazole at two-week intervals is much better.

Defoliation during the growing season is not natural for wild species roses (which are disease-resistant in their native habitats) and it is harmful to garden roses. Upright growers refoliate at the top with ugly bare legs and reduced repeat bloom. Tender roses growing in subzero climates are less able to store fuel reserves and may die over winter or grow out feebly in spring. However, roses that are fully cane-hardy in the climate will survive defoliation and produce good spring bloom before getting ratty-looking after the first flush.

I have roses that would not bloom until I started spraying. The roses get energy from the leaves to bloom. No leaves, no bloom. I have gravitated towards more disease resistant roses, but there are a few I'm not giving up.

NO!
I grow 400 roses in a heavy blackspot area. Over the years I've replaced the worst blackspot prone with disease resistant shrub varieties. I do get a little blackspot and do grow several hybrid teas and haven't sprayed anything for 10 years. My roses do not lose their leaves. Most of my roses are not Knock Outs and many have high centered blooms. I don't feel I've given up anything.
You have to make the choice!

I've done all the research and bought all the "right" roses and they still spotted and mildewed. If I'm going to have to spray, or live with the fungus, I might as well pick the ones I love and to heck with it!

Here here!!!!

Meredith brings up an interesting question: do older bushes fight disease better? I was in DC (for the first and only time of my life) in '09 for a week: I was horrified seeing roses there - thorny sticks without foliage. I'd probably grow hostas and peonies if I lived in that area...or I'd spray and spray and spray. At Dumbarton Oaks - the teas looked okay - less disease - and there was a huge climber there (Alister Stella Gray? I couldn't be sure) that was whistle clean - no disease at all. You all in the Black Spot zones: you are my rose growing heros.

As to more mature roses resisting better, often it is the other way around, as a rose that was resistant for years catches the strain of blackspot that it is susceptible to. Then that form of blackspot will never leave that plant. This happening over and over again convinced me that only a few repeating roses will do well here without spraying.

Henry Kuska, who has grown many hundreds of roses without spray in northern Ohio, says that roses will step up their immune response in response to fungal attack and do better over time. I'm sure that's true, but it's not enough in this climate. I observe a couple of large no-spray gardens planted with roses considered relatively resistant, and most plants look bad from late June on into fall. More susceptible and winter-tender varieties die out. Hardier varieties survive and look good in the first flush. People here should plant more once-blooming gallicas and albas, but with a six-month blooming season for repeaters, we tend to resist that idea.

Many people say that some roses become more resistant to mildew when they mature. I don't have enough experience with mildew to speak to that.

Mildew is something I see more of in dry years (not on roses, on phlox and things like that). So it does make sense that an older roses, with a larger, more efficient root system, would be more resistant to mildew. I've never known a rose to grow out of blackspot.

I have not tried the organic sprays except for lime sulfur dormant spray, and though it is organic it is very bad to breathe the stuff and is definitely toxic to bugs. I bought some organic bug killer one time that was terrible stuff to breathe and blackened a plant. Organic isn't necessarily non-toxic.

Anyway I spray the chemical stuff but not so much in the heat of summer. I don't quit spraying in summer, but less. Roses can keep a good percentage of their leaves with less frequent spraying. It might be a good experiment to try using a weaker concentration of fungicide also. I used to use Messenger and thought it helped. Suppossedly it increased the plant's natural immunity. I don't know why they took it off the market.

I have similar experince to Michael's. Some roses can be resistant for a year or two, but than they will get BS and from that point on, it is horrible. They become BS magnets and sometimes even die from BS. Midas Touch, Baby Love, Morning Has Broken , Colette were examples of such roses in my garden.
Olga

Seil and buford - nice to see some rational thought about fungicides, at least. :-) For me, Bayer is a godsend. I prefer to grow many of the roses that my parents had and that I grew up with - Tiffany, Crimson Glory, Peace, Mister Lincoln, Queen Elizabeth, etc., etc. I started using Funginex two decades ago, but it's really not much better than a horticultural oil. That's about what it is, except petroleum-based, I think.

Anyway, I switched to Banner Maxx when my numbers of roses grew. Even with close to 90 hybrid teas and floribundas and sometimes 12 gallons of spray at a time, though, most of it would go bad in a couple of years before I could use it all. Then there was the constant mixing with Indicate 5 or something similar (a real hassle). With the Bayer, I don't have to worry about any of that. It may cost more per gallon than buying the bulk Banner Maxx, but at least I'm not wasting it.

Just to see a black spot infected leaf actually improve, and not completely die off, is a modern wonder.

I have powdery mildew so badly on Veilchenblau that it's killing the bloom. My fault, I have it planted where it doesn't get much morning sun. The weather this year has been ripe for PM. I was out there just now and many of the clumps of buds are grey and fuzzy and dying. It's so big that I'm still getting many flowers. But this is the worst I've seen and the plant is 5 years old.

There are some roses I wouldn't plant again because the are BS magnets. But there are some I would grow regardless. What I like about the Bayer is that you spray it every two weeks (I spread it out to 3-4 in the very hot months), it's systematic so once it dries, it can't be washed off and it will penetrate the plant, and it will stop a BS outbreak in it's track. I think with anything organic, you'd probably have to spray every few days. At least around here.

Olga, you never answered me if Abe is still gloriously reigning in your magnificent garden....hope you still grow him! :-)

Thanks everyone for your great answers. We have lots of mildew here this year. I spray some roses with Bayer - only the ones that really get stunted by the pressure of the fungus: Devoniensis (shrub form); Mme. Lombard; Condesa de Sastago (the Ultimate Diva Rose); Alliance Franco-Russe and Rosette Delizy. Other than that, everything's on it's own.

The following was stated: Henry Kuska, who has grown many hundreds of roses without spray in northern Ohio, says that roses will step up their immune response in response to fungal attack and do better over time."
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The immune system is only part of the explanation. Beneficial fungi are considered to build up to the point that an equilibrium with the blackspot is reached after about 5 years.

Here is a link that might be useful: earlier thread

Sorry, Jerome. Abbe is here, but it suffered a lot after I stopped spraying 2 years ago. This is an example of how a rose can decline here if it is weakened by BS. It is probably 1/5th of its old size and I am seriously considering take it out this year. I really love this rose, but to see it naked and ugly from June till November is heartbreaking. I sprayed my roses for many years. I feel like it is time to grow what is healthy and happy here. But a lot of my old loved roses suffer from this decision. I also had really bad hits from RRD during last two years. My Lady Hillingdon, Yolande de Aragon, Le Vesuve, Constance Spry and some others are gone.
Sad, but I still will grow roses.
Olga

Beneficial fungi is something I definitely have in my rose-growing soil. Maybe that's what it is? My grandmother's old trick to planting anything was to get a scoop of wood's dirt -- like compost from the woods, and so I've always done that. I live in her old woods :)

I'd spray a favorite rose or two all season to keep growing it, absolutely. I just prefer to see what can keep up by itself. I grow so much that I hate all of the extra work involved, not to mention being afraid of upsetting the balance of nature here.

Insecticides are different, imho, because I have so, so much insect life here. I feel really bad about having to use those, even on one rose.

I changed out my irrigation from sprinklers to soaking hoses under mulch and little micro sprayers on the flexible small tubing. It was a big difference. A few plants had the spots very bad a few years back. The following January, I cut them all down very low and removed the old mulch. Then I sprayed but since there wasn't much plant to spray and what left was very low, I didn't have to use much spray or risk getting it near my face. Then I put ripped up cardboard down like Karl says to prevent weeds and put down new mulch. The plants act like they never had it at all. If it ever gets bad again, I will probably do the same thing. It didn't take that long for the plants to grow up again.