Roses forum→What is causing this problem with our roses?

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Name: Rado
Toronto, Canada
radoslav
Jun 5, 2021 10:43 AM CST
Hi all,

we're new gardeners and know pretty much nothing about cultivating flowers.

We're located in Toronto, Canada.
We planted 6 roses plants 2-3 weeks ago.
We started noticing issues with mature and new leaves (pics attached).

What is attackking our roses and how to best remedy this?
Thumb of 2021-06-05/radoslav/90b4bb
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Thumb of 2021-06-05/radoslav/8a5106


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ElPolloDiablo
Jun 5, 2021 12:31 PM CST
Your plants were attacked by aphids while they were actively sending out new buds earlier this Spring. What you see is typical aphid damage: scar tissue and deformed growth. The aphids are long gone and the problem now is merely cosmetic: those leaves will just look bad as the season progresses.

There are literally dozens of species of aphids attacking ornamental roses: they are generally active in the Spring when growth is resuming. That's when you should keep an eye on your plants for them. They manifest themselves as large clusters of tiny insects on new growth.
They can be eliminated by using insecticides, washing the new growth (throughly! Over 90% of aphid populations are females capable of partenogenesis, so miss a few and they'll be back sooner than you like) with a water jet or smothering them by spraying them with agricultural mineral oil.
The Saviour.

dtdavies
Jun 5, 2021 3:11 PM CST
Those black spots look like some type of fungal disease—black spot or possibly anthracnose. They both lead to yellowing of leaves. The damaged leaves must be removed and disposed off. Keep your garden clean of rose debris and avoid watering later in the day. I also disinfect my pruners to avoid spreading the disease. I am using a fungicide every week to get control of the disease. Once it's under control I'll probably spray once a month. Continue to remove affected leaves.
The curled leaves almost look like thrips damage that requires insecticide.
Name: Rado
Toronto, Canada
radoslav
Jun 5, 2021 3:45 PM CST
Thank you @dtdavies.

Can you share what fungicide you use? Also, is there an insecticide you have used that is effective?

Name: Rado
Toronto, Canada
radoslav
Jun 5, 2021 3:46 PM CST
Thank you @ElPolloDiablo.

What insecticide would you recommend?
Name: aka Annie
WA-rural 8a to (Zone 7b)
Sandsock
Jun 5, 2021 10:59 PM CST
Often roses that are getting over or under watered or under fed (chicken manure) or fertilized tend to get bugs and disease, see if you can check that they are getting what they need and they will often fight off issues. Then go to a good local nursery with photos and get what they recommend....they will probably have the amendments too!

marezeedo
Jun 6, 2021 8:34 AM CST
I'm hoping someone can help me... I have small backyard which is fenced in, (and now it's getting a makeover to be taller), but I had a visitor which ate my tri color flowers & about 1/2 of all the leaves. Will this attack finish off my rose bush, or will it come back? I sprayed it with Liquid Fence, as well as perimeter of yard. Should I prune the branches, or fertilize it now, or just let it be to recover from the shock? I do t want to lose it, it's so beautiful! (I'm including before & after pic). Thank You!
Thumb of 2021-06-06/marezeedo/be15ce
Thumb of 2021-06-06/marezeedo/a3a4e0

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Port d'Envaux, France (Zone 9a)
A Darwinian gardener
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JBarstool
Jun 7, 2021 6:26 AM CST
Marezeedo - a few thoughts...
You don't say what type of rose this is; do you know?
The photo is not very clear but it certainly looks like insect damage so I am not sure why you would apply an animal repellant -especially since you say the garden is fenced-in so I assume you are unlikely to be hosting herds of hungry deer. Maybe I am missing something.
Roses are prey to lots of pests and stressed plants more so...and keeping a rose in a relatively small pot in less than ideal conditions is going to stress it. Roses can be successfully grown in containers but the bigger the container the better.
Will your rose recover? It certainly has the ability to do so - the damage you're showing need not be fatal. But it goes back to whether you can offer conditions in which it will grow.

Please do not use pesticides and chemicals needlessly, often they provide no benefit, can be environmentally questionable and a waste of your money. Here, I'd start by addressing the growing conditions by providing a container with adequate room for vigorous roots, cutting off the damaged stems and encouraging the plant to grow healthily it will then have a better chance of warding off some of the pests that will invariably come.

I've grown to accept a bit of damage to my roses, less than perfect foliage, an occasional infestation of aphids (followed by ladybirds if I'm lucky), and the dreaded Japanese beetles that I remove by hand and send to their demise in a soapy-water filled bucket. As long as I still have plenty of fragrant blossoms I can overlook the problems.

Good luck.
I find myself most amusing.
[Last edited by JBarstool - Jun 7, 2021 6:29 AM (+)]
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Name: Rado
Toronto, Canada
radoslav
Jun 7, 2021 7:01 AM CST
dtdavies said:Those black spots look like some type of fungal disease—black spot or possibly anthracnose. They both lead to yellowing of leaves. The damaged leaves must be removed and disposed off. Keep your garden clean of rose debris and avoid watering later in the day. I also disinfect my pruners to avoid spreading the disease. I am using a fungicide every week to get control of the disease. Once it's under control I'll probably spray once a month. Continue to remove affected leaves.
The curled leaves almost look like thrips damage that requires insecticide.


Can you share what fungicide you use? Also, is there an insecticide you have used that is effective?
Tuscany, Italy
bart2018
Jun 8, 2021 4:58 AM CST
I agree totally with JBarstool-often using insecticides and fungicides is just a waste of money and time, not to mention being bad for the environment and for your health. You definitely should NOT use an insecticide for aphids-they are extremely easy to kill just using plain water, and they help to prevent thrips. The dark areas do not look like blackspot at all to me.

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