Roses forum: What is causing this?

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Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
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LolaTasmania
Nov 1, 2018 1:13 AM CST
My new rose bed was planted in July and everyone of them except Glamis Castle pushed out new growth that was very healthy. I thought GC had BS so I sprayed and the big black spots didn't return but small brown spots took their place. Yesterday I checked that there were no others with these spots and they were all ok. There is also a young tree in this bed which had perfect growth. A moment ago I went to check them as I do every evening and not only is GC covered in these brown spots but other roses have it on the lower leaves as well. It started on the lower, older leaves with GC but it is now covered in it. Even the tree has brown spots and it even has a few pin holes where the spots ate through the leaf.
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This is GC. I had to put my foot below it or the leaves would have been lost in the background.

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GC again.

Thumb of 2018-11-01/LolaTasmania/e35655
A second rose with spots.

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Third rose.

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Dogwood with spots and holes.

The camera wouldn't focus for me so I apologise for the poor quality pics. There has been no humidity or other weather related problems and my neighbours have not sprayed or fertilised their pastures recently. What do you think it could be? I am starting to panic as it has all happened so fast.
Lola.
Zone 9, Sunset Zone 9 (Zone 9b)
Roses
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Mustbnuts
Nov 1, 2018 2:35 AM CST
I am not an expert but are there rusty orange globules on the underside of the leaves? I tried to see if there were any pictures of the underside of the leaves but didn't see them. Just could be my bad eyesight.

It could be rust. GC is known to have fungal issues and I know that Dogwoods can also get rust. Do you have neem oil? If it is rust or blackspot or another fungal disease, neem oil can treat it. It also shouldn't hurt your sheep either (but again, I am no expert). Neem oil may need to be repeated (as far as spraying) once a week or once every other week.
Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
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LolaTasmania
Nov 1, 2018 3:15 AM CST
It is only the upper sides of the leaves that are spotted. The underneath is fine on every leaf except on those that are badly marked by it. I am wondering if it could be something spread by insects like flies that don't lay eggs or eat the plant but exude a chemical that burns the spot they were sitting on? The plants do not look weakened by it too much but the brown leaves are going to stop them from converting sunlight to energy soon so they will be weakened by it eventually.

I will try neem oil (which I will have to look up because I don't know what it is) in the morning and see what happens. Lola.
Coastal Southern California (Zone 13a)
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jerijen
Nov 1, 2018 12:32 PM CST
I can't see all of them all that well, but on the pix of Golden Celebration, I'd say blackspot. (It's particularly subject to it, as is its parent, Aloha.)
In my climate, where the air is increasingly dry, it's a passing problem. But, if your conditions are favorable to blackspot, you might want to know that many yellow roses have that problem.
Minnesota (Zone 3b)
RpR
Nov 1, 2018 2:06 PM CST
Mostly Black-spot, may be other virus but treat with a bio-fungicide, I use Serenade or Sonata ---- though ---- I have spent the bucks for Oxidate but not used it yet.
Costs a bundle so I will use it to to saturate soil over winter.
Black-spot does not disappear, you have to pick off the leaves and dispose off them.
Black-spot may be dead but the rose will look bad and you do not know which leaves are still actively sick, so pick them off.
Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
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LolaTasmania
Nov 1, 2018 2:52 PM CST
The Glamis Castle had it from the get-go and it seems to be the worst infected one. Should I remove it as it seems to be very prone to it and it would always be a threat to the others? We have rain and thunderstorms all day today but I can remove it tomorrow morning and spray all the others then. Should I cover Glamis Castle today with a bucket to stop the rain spreading the disease around? Lola.
Sydney, Australia (Zone 10b)
Protoavis
Nov 1, 2018 3:21 PM CST
jerijen said: But, if your conditions are favorable to blackspot, you might want to know that many yellow roses have that problem.


I agree with that, pretty much every BS infected plant in my garden has yellow (even if masked by a red top layer), everything else is clean. Perhaps amusingly Foetida itself is clean.

Anyone with oryzalin (aka Surflan, Embargo), am looking for a small amount rather than 5litres from manufacturer (min size in Australia....)
Name: Porkpal
Richmond, TX
Charter ATP Member I was one of the first 300 contributors to the plant database! Keeper of Poultry Farmer Roses Raises cows
Garden Ideas: Level 2 Celebrating Gardening: 2015 Plant Identifier
porkpal
Nov 1, 2018 5:41 PM CST
Many roses outgrow their susceptibility to disease as they mature and acclimate to their surroundings. Fungus spores are everywhere, I think removing/bucketing the rose would be over reacting.
Porkpal
Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
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LolaTasmania
Nov 1, 2018 6:14 PM CST
Thanks for the advice everyone. I looked up reviews on Glamis Castle and it was discontinued a few years ago because among other negative traits it was very susceptible to BS. Some reviewers loved this rose even though it was a challenge to grow but others got rid of it and didn't miss it at all.

I sat upstairs in my library (not as glamorous as it sounds) looking out at the new garden bed and thought about how Glamis Castle is like a BS magnet and that as long as it is there it will be infected and a danger to all the others. The rain stopped so I ran outside with a shovel and a plastic pot. The ducks thought the pot looked like their food bowl so they followed me up the hill and watched as I dug up the rose and collected all the spotty leaves from the ground. Thunder and lightening began in the west and the rain started again but I kept going. I went from plant to plant and snipped off all diseased leaves and put them the pot, tripping over ducks as I went. I made it back inside just as the storm was above me with thunder and lightening cracking overhead.The rose is now in a pot far away from every garden bed. The leaves I put in the fireplace and I disinfected my shovel and snippers.

I may have overreacted but I feel less stressed about the whole thing now. When the sun comes out tomorrow I will spray all my roses to help prevent spores spreading from plant to plant. Lola.

Minnesota (Zone 3b)
RpR
Nov 1, 2018 7:18 PM CST
Treat the soil or all your work is for naught.
Get a natural fungicide and saturate the ground, several times a year.
That will not totally stop it but keep it under control.
Zone 9, Sunset Zone 9 (Zone 9b)
Roses
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Mustbnuts
Nov 1, 2018 8:23 PM CST
Lola you are so industrious! Not sure I would have been out there with that weather. Sorry you decided to get rid of your Glamis Castle. Try the neem oil and see if it helps.
Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
Image
LolaTasmania
Nov 1, 2018 9:15 PM CST
If it survives in the pot and behaves itself I will replant it in the same spot next winter. It may outgrow it's propensity for BS as it gets older. I will dig up a lupin seedling from the other garden tomorrow and put it in the hole it left so it won't look so bare this summer. I don't want to put another rose in there until next year in case there are still spores waiting to pounce.

This month the National Rose Garden at Woolmers, only an hour away from me, has its rose festival and I will go along to see what grows well here. Woolmers is an historic property with fabulous outbuildings and gardens that are open all year round but the rose festival is when everything is at its best. I have put a new memory card in my camera just for the festival so I won't have to rely on my own memory so much.
Zone 9, Sunset Zone 9 (Zone 9b)
Roses
Image
Mustbnuts
Nov 2, 2018 6:11 AM CST
Lola, your plan to visit the garden sounds wonderful. Hope you will share pictures with us from your trip. Most of us in the northern hemisphere should have our roses pruned by then and we will be hungry for seeing pictures with blooms in them.
Name: Shyam
San Francisco, CA (Zone 10b)
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Rose_Guy1127
Nov 2, 2018 2:29 PM CST
@LolaTasmania: I've been where you are before. The stress of constantly fussing over the roses battling with fungal diseases. Even though San Francisco weather considered as rose heaven, it is also favorable for BS, rust, and mildew. I tried all sorts of organic mitigations to battle the issue. Some provided temporary (say a couple of days) relief to the roses; then it's the same thing all over again. Peers at the SF Rose Society warned me early on that it is tough to grow roses organically in the City. Tending to rose issue on a daily basis only added to my stress. In the end, I decided to cross over to the dark side of non-organic means and went with Bayer disease control spray. It has been three months now, and my roses are free from BS, rust, and mildew. I am not advocating in using chemical spraying but sharing my experience while empathizing with your experience.
Name: Lola
Tasmania
Keeps Sheep Roses Cottage Gardener Garden Photography Birds Farmer
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LolaTasmania
Nov 2, 2018 4:11 PM CST
Thank you, Shyam. I have been using home remedies like milk spray, bi-carb mix, and things like that because I try not to use chemicals unless it is the only way. I think removing that one rose will help the others better than constant spraying will. I do have a Bayer spray in the shed which I will use only on the rose I removed to see if it improves it better than my natural sprays.

The climate where I am has no humidity but the temperature range is BS heaven so I may have made myself a 90ft by 8ft patch of misery in filling it with DA roses, but at least I will learn from the experience. My village is known as the 'Village of Roses' and I asked one of the rose ladies today about my new garden and she said I must love the look of BS seeing as I planted only DAs. The village is lined with OGR so they are always healthy looking and only need attention twice a year. I should have asked her before planting anything but I have not had much to do with the roses ladies as I find them slightly intimidating.
Zone 9, Sunset Zone 9 (Zone 9b)
Roses
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Mustbnuts
Nov 3, 2018 6:42 AM CST
Wish I was down there. I would go with you to talk to the "old rose" ladies. I am sure they have some interesting stories to tell and would be quite educational to boot. Do try the neem oil. It is organic and you may have to spray weekly but give it a shot and see how it does. It may help.

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