Will Monterrey Complete Disease Control fix this?

[JScott]

This isn't about an orchid issue, so I considered in posting in the forum for completely off topic, but it is about a disease, and this could apply to orchids, so I posted here.

I have these roses that I've had no trouble with all year. Not a single blemish. Now I have two plants starting to show signs of disease. I googled, and couldn't find any pictures that looked exactly what i have, but maybe rust or powdery mildew or black spot? I just can't tell.

Anyway, I have plenty of Monterey Complete Disease Control on hand, so I sprayed them with that yesterday and drenched the soil. I'll spray again today and drench the soil again in another couple days. Do you think Monterey will work on these diseases?

They are both hybrid teas. One is Opening Night and the other is Desert Peace. It's the first year for both them, but they both have thick sturdy canes (and I also did an experiment. ES challenged the conventional wisdom that in warmer climates you should plant them with the graft union level with the soil, but he said that was BS. You should bury the graft union under any circumstances. So I planted Opening Night as I normally would, but I planted Desert Peace with the graft union below the surface of the soil. Opening Night did just fine; what I would expect form a first year tea rose, but omg Desert Peace... it just went wild. It looks like a second year rose, or even a third year rose. I have a bunch more ordered that will arrive in late February, and I'm going to plant them all with the graft union below the soil. Just a little side note there).

So you can take a look at the pictures and tell me what I have. I don't really care much what disease it is exactly; I just want to know how to treat it, and since Monterey is what I had on hand, that's what I used, and I want to know if that was an acceptable choice, or if I should try something different. It isn't bad yet. I think I've caught it early enough that I can easily wipe it out. Any thoughts?

[SouthPark]

Could check this link JS.

link here

[JScott]

That's a great resource! Thanks for the link, it may help a lot. I was really wondering if anybody had had any success using Monterey Disease Control to control disease in roses, but if my Monterey doesn't work out, I have plenty backup plans in that article.

Monterey uses a combination of natural bacteria which supposedly overcome the disease causing agents, so it is environmentally friendly. I'm not against using harsh chemicals in my garden if I have to, but I try to save that for a last resort so I'm not pumping too many toxins into the earth, so that's why i prefer to try Monterey fist, but if that doesn't work, I'm not against using any of the products listed in that article.

Thanks again; that's helpful.

[estación seca]

It looks like black spot disease.

[JScott]

Originally Posted by estación seca

It looks like black spot disease.

My understanding is that is a pretty difficult one to deal with. Maybe I'd be better off using a chemical product than a natural one. I'll spray with the Monterey a couple more days, and if I don't see any improvement I'll move on to my RoseRX 3 in One (basically Neem oil), and if that doesn't work, I'll try my BioAdvanced (Imidacloprid - 0.47% Tau-Fluvalinate - 0.61% Tebuconazole - 0.65%)

[estación seca]

I think it's fungal, spread during high humidity. The spores overwinter on shed leaves and plant stems. They splash up onto plants the next spring. Make sure you rake up all dead leaves, and bag and remove all prunings.

Consider using a wettable sulfur powder. It is an excellent topical fungicide. Spray the canes during a good dry spell this winter with Bordeaux mixture (copper sulfate.) I would read up on your antifungals to make sure they cover black spot before using them.

We're lucky here; it's not humid enough for black spot. We do get powdery mildew during spring and fall days when it's cool with very low humidity.

[JScott]

Originally Posted by estación seca

I think it's fungal, spread during high humidity. The spores overwinter on shed leaves and plant stems. They splash up onto plants the next spring. Make sure you rake up all dead leaves, and bag and remove all prunings.

Consider using a wettable sulfur powder. It is an excellent topical fungicide. Spray the canes during a good dry spell this winter with Bordeaux mixture (copper sulfate.) I would read up on your antifungals to make sure they cover black spot before using them.

We're lucky here; it's not humid enough for black spot. We do get powdery mildew during spring and fall days when it's cool with very low humidity.

I never had black spot in Oklahoma. Mine would get scale in the winter time sometimes, but a good application of horticultural oil took care of that. The disease control products I have both say that they treat black spot, but I think they all say that. I'll do some research, and probably end up doing the sulfur thing you suggested. It can't hurt.