Spray for what? A lot of us don't spray at all. A lot of the sprays are pretty horrible to the environment. There's a lot of discussions here on the forum about what to spray for what and the consequences of spraying (and not). Read those before you jump into it.

Personally, I wouldn't spray at all until you discover whether or not it is even as issue. Roses have survived for thousands of years without being sprayed.

I assume you're concerned about blackspot. With your roses I'd wait and see. John Cabot probably won't blackspot at all and the other two roses might get only mild cases that you can live with. I wouldn't characterize any of the usual rose fungicides as "pretty horrible to the environment" but I would agree that not spraying is better than spraying and it's certainly less work.

Modern synthetic sprays formulated with either propiconazole (Bonides' Infuse, for example) or tebuconazole (Bayer products) will not heal blackspot scars but they will kill the infection and prevent future attacks. If you decide you need to spray and you want to go with the synthetics, the usual practice is to spray on a regular schedule starting with leaf-out.

If you decide to go with organic sprays, try elemental sulfur. I suggest forgetting about Neem oil. It's no more effective than other, cheaper, vegetable oils.

Presumably, you tried to get 'very disease resistant' roses so you don't have to spray. So if you do have to spray them, they aren't what you want in the first place.

John Cabot definitely won't need to be sprayed. Mine only gets sprayed when I have a lot of extra in the sprayer and need to get rid of it. I've never seen any blackspot on it and I get plenty of BS on my other roses. On the other two, just wait and see if you do get BS then try the Bayer Advanced that doesn't have any insecticide in it.

I bought just the Bayer Advanced fungicide, not the insect control and NOT the 3-in-1 or the All-in-one. I haven't used it yet. Yes, I bought the two roses after A LOT of research into which ones should be resistant. Key word: should be. I have also read that to treat BS, you have to use sprays as a "preventative" measure, and not after it happens. That's why I was thinking of doing it now. However, I will take the wait and see approach. Easier for me! lol
I know that I have had roses before that were not right for my area (got shovel pruned already), and they would BS half way up the bush about July and August (right when my JB's show up).
I am glad to hear that John Cabot should do well without spray.
I actually did do a lot a research before purchasing these. However, I actually bought them because I didn't want to winter protect. We'll see about that too lol.

Kentstar, I should have mentioned in my post that the usual advice in rose books is that fungicides are preventative and not curative. Hence, spray at the very start of the season and don't skip a beat. But, some very careful research has shown beyond doubt that at least three fungicides are curative as well as preventative: potassium bicarbonate, myclobutanil, and tebuconazole.

You spray preventatively if you know there will be a problem (e. g. all hybrid teas and most other roses will get blackspot in the eastern half of the U.S.). Let your plants go for a season and see how they handle it. If you need to start spraying tebuconazole, it will stop the disease from spreading and will cure leaves that aren't too far gone.

John Cabot is resistant even here.

I also search for BS-resistant roses, but there are degrees even within that category, so I adapt and limit my spraying to the characteristics of the roses.

For instance, I divide my roses into three general categories: those that never or almost never need spray (like Austin's Mayflower); those that sometimes need a bit of help during the height of BS season (my climbers like Eden may get sprayed a couple times during BS "season"--spring and fall in my zone); and those that will be the first to blackspot and may need 3-4 sprays in spring or fall (that, as you may guess, includes most of the HTs and grandifloras). I almost never spray during July and August because it is usually much too hot here for BS to survive, much less thrive.

The only way you can determine which category your roses belong to is to not spray for awhile until you can actually see how resistant the rose is. That means you need to check frequently with new roses--until you learn their habits. I've had my roses long enough that I know which ones are likely to first show BS--when I see a spot or two there, I know its time to spray the more susceptible ones, but I limit the spray to those that are in that category. THen I keep an eye on the second category, and my second spraying may include them along with the first group. The third spray may be limited to the first group only--unless I see problems beginning to develop on the second group also. For spraying purposes, I largely ignore the third group, unless I see a specific problem--which is almost never.

Since I hate to spray, I figure why spray more than absolutely necessary. The more you know your roses, the better able you will be to decide if it is necessary or not.

Good luck

Kate

Wouldn't it keep the rose healthier, which is what I need to do since I just planted it to get it through the winter here? I have read that the healthier a rose is going into winter, the better chances of survival.
Forgive the questions, I'm still very new to this and am learning as I go.
I would rather not have to spray at all, tis true. Easier for me, and easier maybe on the rose.

Then there is the old line about elephant repellent. It must work since I've never seen an elephant in my garden :-)

Why would you spray a healthy rose to prevent a disease it isn't going to get? And if it is going to get this disease you don't want, then why do you want the rose in the first place?

Who is in charge of this garden? You or the inmates?

If you don't want to spray, don't spray. It really is that simple. The only reason I even own a sprayer is because the bay tree gets scale that takes a few squirts of horticultural oil to deal with every now and then.

Blackspot weakens plants by attacking each leaf separately from the outside, not systemically. "Healthy" in this case means keeping, say, 75% of the foliage healthy through the fall, so the plant can grow strongly all season and store a full quota of sugars and starches. The roses you have chosen may be able, in your climate, to meet this standard without any help from spray. Many chemicals slightly reduce plant vigor with regular use.

If you get enough sick leaves to justify action, you can check the disease with tebuconazole.

If you were planting hybrid teas, we would tell you to spray at least every two weeks from leaf-out to mid-fall.

The only one I would consider spraying now is the Maria Stern "Sub-zero" hybrid tea. Just because she is a "hybrid tea".

You could spray her, or you could wait and see how long before spots appear on the lower leaves. Brownell's roses are not typical hybrid teas. I don't know anything about Maria Stern except from pictures.

Maria Stern should only need to be sprayed for blackspot if the weather is hot and humid for extended periods of time. In south western Ontario we get extreme conditions like that. I don't remember Maria being too bad, but there was some which is not unusual here. A new rose and clean soil surface will mitigate black spot pre-conditions. To treat for blackspot you must spry every two weeks and re-apply if it rains. Watering at the base of the rose and not from the top and the time of the day also reduces blackspot development, as does keeping the rose brush pruned for optimum air flow. It is not wise to spray when very hot, it is possible to damage the foliage. Prevention by good practice is easier than spraying and cheaper. Good gardening , Susz

She'll definitely have good air flow, as she is on the side yard by herself. She has no other plants right around her either. So, that's good. And I know to keep the watering low and not overhead. Thanks to all and your knowledge. I think you are right. I will wait on the spraying :).