Acetic acid fights rust, black spots and powdery mildew. To make this spray, mix two tablespoons (30 mL) of cider vinegar in two quarts/litres of water. This spray should only be used in the morning or early evening, when it's cool and there's no direct light on the plant.

Has anyone tried this?

They also recommend the usual baking soda, garlic, horsetail, seaweed, onion greens and horticulutal oil.

If black spot doesn't like alkaline environments, would ammonium hydroxide(Ammonia) work? I've sprayed it on other plants. Not to prevent BS, but to give them a shot of nitrogen.

3 tablespoons of Apple Cider Vinegar to 5 litres of water. I couldn't begin to tell you how impressed I was at the results! Double Delight, which used to get riddled with blackspot looked lush and healthy with no b/s to be seen!

Also as an experiment I sprayed on the vinegar spray and waited to see how long it would take for more blackspot to appear, and it took approximately 3-4 weeks for the more blackspot prone roses and even longer for the healthier ones,( the Austins ) if at all!

As for only spraying in the early morning or early evening, I found that that didn't matter either. I sprayed during the middle of the day ( in spring, mind you! ) without any burning.

Another method I have adopted now is to spray with the vinegar spray and then alternate with the milk spray - 1 part milk to 7 parts water. Works a treat! I'm so happy to find such a cheap and harmless solution, and by harmless I mean that you can get away with having your skin exposed, but I still wear sunglasses as the vinegar solution could burn your eyes if it blew into them I suppose! All the best and happy gardening!

Here's another method I adopt to occasionally. When your rose leaves are showing sign of deficiency, like yellow leaves etc, simply spray on a solution of either liquid seaweed and water or fish emulsion and water and the leaves bounce back within the week of spraying. I use a small hand sprayer that is about 450 mls. Add only half a teaspoon of the liquid seaweed or fish ..... that's all you need! And that's all from me ......... over and out!
:-D

Millie

The weeds I've sprayed and poured vinegar on seemed totally unaffected. It may work on some, just not the ones I tried it on.

Dark Rose, did the vinegar kill the black spot that was already there? Did it actually kill the black spot, not just preventing it from spreading further?

-Silly Angie

Around here, people use white distilled vinegar to kill the weeds that come up in the cracks of sidewalks. Takes a few days but soon they turn brown and can easily be brushed away.

I've always had very good luck with Miracid, but I'll try that vinegar, there's some BS leaves I've neglected lately and always love to try new remedies.

We have been back to Florida now for over a month and have been using baking soda alternating with fish and seaweed. So far it seems to work as BS is not spreading.

I only have few roses here and most were all defoliatd except Belinda's Dream. They have started to improve since we have been back.

Cornell forumula did not work for me last year. It seems it needs to be alternated with something else at least that's what I am finding out.

The milk&water probably calls for a full-fat milk, because it forms a film over the leaf that prevents blackspot from taking hold. Works like CloudCover and other like products.
The fat in the milk is what forms the film so heavy whipping cream would be even better : )

with all the best, e-le'phant

I have been trying to find a non-chemical spray that works. After a disastrous season last year going cold turkey with the Cornell Formula I'm back to chemicals while I try to find an alternative.

After all the rain we've had a did spray with chemicals but the vinegar held the bs off for a week very nicely. I will be experimenting with it more.

Sounds like the Atkins Diet for roses! :)

From, "Growing Roses Organcially" by Barbara Wilde:

"Black spot spores need a near neutral pH to germinate, so anything you can do to lower the pH on the surface of your roses' leaves will help prevent the disease............."

Hence the suggestion for using vinegar.

Also: "Before air pollution control laws, black spot was less common in urban areas because acid rain (caused by sulfur containing pollutatnts disolved in rainwater to make acids)."

Hence the effectiveness of sulfur.

And: "........For instance a solution of skim milk applied to rose foliage will do a pretty good job of inhibitin g black spot. The theory is that as the milk spoils on the leaf surface, lactic acid and casein are produced. Lacitic acid lowers the pH, while the casein helps bind the milk solution to the leaves."

I don't know if cream is better for black spot than skim milk---I know vitamin E is found in the fat of milk, I'm betting on the side that lactic acid is not since her suggestion is for skim milk. And she suggests a ration of 9 parts water to one part skim milk.

Also: "At the other end of the pH range, sodium bicarbonate prevents fungal diseases by increasing the pH on the leaf, making it more alkaline."

She suggests 1 tablespoon per gallon of water, with a light hort. oil or veg oil, along with a squirt of mild dish soap to help it stick to the leaves.

She also warns that the sulfur products "adversely impacts some beneficial insects and mites, so consider it a last resort in your disease management program."

Good luck!!!

Keep in mind that pennies made after 1982(? I think that's when they changed them) are copper-coated zinc - and very thinly coated, I might add. So if you wanted more copper, you might want to either go with older pennies, or get a few short lenghts of copper pipe...

I am using vinegar for two reasons:
1. Vinegar will speed the copper erosion
2. Rain water is more acid
3. I need the spray to have a PH of 5.
I have been doing a great deal of reading about copper toxicity. It seems that the actual amount of copper I would get from a week or more soaking would not be harmful to the plant. But if I wanted to be conservative I would soak over night.

I believe based on the link below that one important focus should be on getting a PH of 5. So I will add the solution to water in a hand sprayer until I reach PH5. I will definitely try this on one bush to make certain that the copper does not affect the plant over time.
Myenawine,
I did in fact think of the penny composition, however since copper seems to work and zinc seems to work, either from the pennies may be OK, as long as I don’t a third chemical resulting from the zinc/copper combination.

I am in the hypothesis and test building phase. I will let you know the results.

Thanks

Why not just buy a copper soap (fungicide) designed to prevent blackspot?

I'm completely new to growing roses, so I've been going the cheap route until I'm able to convince myself that I either know what I'm doing, or at least won't kill 'em right off the bat - the $3.99 bareroots from Walmart, etc.

Picked up a couple potted J&P's from Lowe's a couple weeks ago - pretty beat up, but salvageable. For those of you who care, Chrysler Imperial and (IIRC) Princess HTs and Iceberg Floribunda.

Anyway, the Iceberg started showing black spot virtually overnight. And not just a little bit- as we say down South, it was ate up with it- like 3/4 of the sparse number of leaves still on the plant. So I tried it: 1T yellow vinegar in 1qt of water, and I sprayed 'em all down - just to be safe. Then it rained off & on for 4 or 5 consecutive days. When I got back outside last weekend, not only had the black spot abated, but the plant had revived nicely (not attributing to the vinegar, of course) and is starting to leaf out and look really good.

Olga

Olga, I'm interested in your list of roses that can go organic in MD, if you wouldn't mind posting it. Thanks!

Climbers:
1. New Dawn -Some BS and Cercospora in the fall, but still thrives, blooms and grows well.
2. Awakening - the same comment as New Dawn
3. Parade - more BS then New Dawn, but still grows and blooms well. Doesn't loose it's vigor becayse of BS.
4. Illusion - very little BS, great climber. Blloms a lot, fragrant
5. Alberic Barbier - once blooming rambler, healthy as a horse
6. Mermaid - not a spec of desease
7. Westerland and Autumn Sunset - loose abourt 50% of their leaves. Still bloom and grow

Repeat blooming roses:

1. Knock Out -(as well as Pink and Blush) no desease
2. Darlow's Enigma - almost no desease
3. Carefree Sunshine -less then 10-15 % leaf loss. Blooms and grows well.
4. Morning Has Broken - less then 10 % leaf loss, great rose
5. Earth Song - Similar comment to Carefree Sunshine
6. Mutabilis - approx 50% leaf loss but still very vigorous and blooms non stop. Never looks ugly.
7. Lyda - The same comment as Mutabilis
8. Safrano - 50% leaf loss, still blooms, but a lot of winter dieback
9. Jaques Cartier - very little desease
10. Marie Pavie approx 30%-40% leaf loss from BS, still blooms and grows.
11. Belinda's Dream - some BS (20-30%). Blooms and grows well but a lot of dieback every winter and first flush almost always balls.
12. The Mayflower - some BS. Gets better with age. Blooms and grows well.
13. Souvenir de la Malmaison - get BS (30-40%) but blooms and grows well
14. Roseraie de l'Häy - no desease
15. Some other rugosas (old varieties with typical rugosa leaves, not morden rugosa hybrids)
16. Arethusa - get BS (30-40%) but blooms and grows well, some die back
17. La Vesuve- get BS (30-40%) but blooms and grows well, some dieback
18.Georgetown Tea -get BS (30-40%) but blooms and grows well, some dieback
Once Bloomers:(There are many healthy once bloomers for MD, they grow and perform absolutly wonderful here, really carefree, highly recomend)
1. Konigin von Danemark Alba, no desease
2. Ispahan - Damask , no desease
3. Charles de Mills -gallica, no desease
4. Belle de Crecy -gallica, no desease
5. Belle sans Flatterie- gallica, no desease
6. Alice Viena -gallica, no desease
7. Jeny Duval -gallica, no desease
8. Tuscany Superb - gallica, no desease
9. Duc de Guich - gallica, no desease
Many other gallicas, I just leasted my favorite ones.
10 Felicite Parmentier -some BS (not much) and PM (when young), but still vigorous, blooms have unbelievable fragrance, looks good

I probably forgot something some others, but it is probably enough for now.

Good luck.
Olga

I am contemplating replacing them with disease resistant varieties. As this is my first time growing roses, I am not at all sure of how to go about doing this. I have about 20 different roses, but if bs is in the soil as someone posted earlier, won't I be exposing my new roses? Just how resistant are the resistant varieties?

Thanks!

I've just decided to try this today. I put 4 T. of cider vinegar to 1 gal of H2O(rainwater) + 1 T. vegetable oil and a squirt of dish soap. I plan to use it every 4-7 days, until the black spot is gone. I'll let you know if it works!
I decided to try this mix from the mixes I saw in the thread. With all the rain we've had this spring(much needed!)black spot has hit a few of my bushes hard. I didn't know what it was at first. Some of my bushes hardly have a spot on them but my climbing roses have been hit hard. One has lost most of its leaves, almost overnight. I really hope this works! I need to mulch with compost too.

I get very good results with vinegar, but I also select roses that are BS resistant.

As you imagine I am more than a little distraught. It was a tremendous amount of work ... 33 plants total. I did not know the BS stuff was that dangerous.
Last year there were spots but they are brown and not like the pictures I was able to find. A couple of days ago I found this:
http://ohioline.osu.edu/hyg-fact/3000/3072.html
Then, last night, this thread.

This AM I used an Ortho Dial-a-Spray sprayer and a bottle of distilled white vinegar to apply the vinegar and water solution at 1.5 ounces per gallon. ( That's equivalent to 3 tablespoons per gallon. )
I sprayed them twice ( to get both sides I can reach ) and the ground too. Pretty soaked but not to the point of having standing water.

I surely hope this works 'cause I cannot repeat the planting ...will have to rip them out and put up a 'real' fence.

Should I cut off any yellowed canes? Can I save the plant that has no leaves by cutting it back to the bud union?

I don't have cider vinager, just plain white vinager.

I made a small 541 ml bottle recipe is.

1/2 teaspoon of white vinager
1 teaspoon of canola oil
4 drops of dish soap
balance filled with water

With living in Vancouver BC, Canada (Pacific Northwest area) and all the rain we still get in the spring. I do have roses that are very suspible to BS.

I have now tried this recipe in the past 2 weeks. I have noticed today that the rose bush I sprayed 50% of the BS is almost gone and no new BS is showing up on the leaves that never had any in the first place.

I am really happy to see this working much better then any chemicals i have ever used in the past. I hate using chemicals on my roses because my bunnies just love eating my rose from my garden.

So not to have to use chemicals on my rose I normally pick off all the leaves with BS, to times there was no leaves left on the rose bush. Everything has to start a new.

It looks like this year I will not have any bare roses at all this yr.

I wish I had found this forum along time ago and know about this recipe. Becuase the rose I have always had trouble with is the same rose bush my bunnies just love the most, is the Dr. Brownell and is chrome yellow with a great scent.

So nice now I just have to give the rose a good wash under water and know the vinager, soap and oil will just wash off. Where if I had to use chemicals they can't get their favorite rose all season long, of worry I am make my bunnies very sick or poison them.

Thanks everyone you have all been a great help, and now have a soluition for this BS problem and to my bunnies health as well.

They are just going to love you this year because they will get thier favortive rose this year.

Janice

Since I started this thread way back didn't realize it's still going on but want to let you know I am alternating with my sprayings. Baking powder does work for rust it seems but not for blackspots at this location anyway as last year my roses were covered with blackspots. It's still early in the season hope they stay healthy looking.

Another new recipe I came across is mixing ASPIRIN 325mg, uncoated, generic aspirin, dissolved in 1/4tsp vinegar, added to a gallon of water, plus a tsp dish soap will also stimulate "systemic acquired resistance" in your roses. (and tomatoes, and bee balm and...everything else in your garden!) Foliar spray once every 3 weeks.

Maybe I will try that one and just add one teaspoon of Dormant Oil for the thrips.

Millie

It also worked in the garden for aphids on the tom's and some kind of bug and fungi on the cuc's.

Neem product is approved for organic growers.
E.g., see http://www.neem4organicfarming.com/

Unfortunately it does not kill or chase off ants or squirrels ...

I have since found that these "Simplicity" plants are advertised as "hardy" but J&P fails to mention the BS. Now I know why. They are terrible for BS which means I have a once a week - 10 day spraying for the rest of my (or their) life from March until October- NOTHING simple about that!
WoW: NEVER buy Simplicity Hedge Roses from J&P if you are in the South(cannot speak for dryer areas). ...

Now if I could only find something to get rid of aphids not that I have many but even on few buds it's too many. They keep coming back no matter what I spray with. Last time I used Murphy's Oil with Listerine yellow mouthwash.

Ecco. Over the years I have seen different versions used of soap some use a squirt few drops and others go for a tablespoon. Try few drops and next time increase to a teaspoon and if no burn shows up keep it at that. Canola oil worked for me so did Horticultural oil too. It does need to be repeated.
Millie

I live in zone 5 and I'd say this year was the best year for blackspot I've seen, so it may not be the vinegar but also the weather pattern. I don't spray at all and my one BS prone plant didn't really have any problem until mid to later August, whereas usually it will begin showing a problem in late June but July for sure. Probably not coincidentally, we had the driest June and July that I can recall...it was a moderate draught. And August was the wetter month, so this is the exact opposite of the usual summer in the midwest!

I think that may have played a large role in BS for this year.

I did get mildew on couple of roses just recently and sprayed with baking soda and it took care it.

What a great thread--long may it live!!

I'm down here in St. Pete-mid-central Florida-and the Fall has been wetter than the Summer (usually it's the reverse.)

This is the second year I've kept roses in containers on my apartment balcony; it's been a rousing success I must say. All on Fortuniana rootstock--Europeana, Love Potion and Bronze Star enjoy the eastern exposure and near-constant south breeze of the 2nd floor.

As organic_appliquelady in Vancouver, BC mentioned, I've practiced the same style of housekeeping--picking off all of the BS infected leaves and leaving it at that. This seemed to work well by itself last year when all I had was Europeana, but this year--wasn't enough to stop the dreaded BS.

At first, tried regular sprays for maintenance, but started to feel concerned about all the non-friendly stuff I was using. Plus, was concerned about neighbors safety too...organic is the way to go!

I fell in love in Love Potion when I saw her at the nursery a few weeks ago; although she obviously had a case of BS, she looked to be a strong, well developed plant that was tidy and shapely in appearance.

At first tried Rose Pride...not much luck. The poor dear kept dropping leaves quicker that she could make them, yet valiantly was continuing to bloom (roses are some tough plants!)

Next, tried the recipe that organic_appliquelady applied:

1/2 teaspoon of white vinager (increased to 1.5 tsp)
1 teaspoon of canola oil (I had only olive oil on hand)
4 drops of dish soap (increased to 12 drops)
balance filled with water

and I happened to have a small, 22 oz. spray bottle that worked great for this recipe; it made enough to treat all 3 of my roses. I sprayed just after sunset on 11/15 and said a prayer.

Well, here it is only Saturday, and Love Potion hasn't dropped any more leaves & the others don't show a further spread either.

Another treatment that caught my attention was the Neem oil--will be getting some of that to alternate as preventative maintanence if the above recipe works.

Thank you so much everyone for sharing your ideas!!

Susan

Susan

Powdery Mildew
The Vinegar Rinse
2 tablespoons white or cider vinegar (5 percent)
1 gallon water

Soak the entire plant, making sure to get the undersides of the leaves. Spray in the morning. Apply once a week as needed until the weather warms up.

Black Spot
Mix ordinary fat-free milk with water in a 1:1 ratio and apply it using a spray bottle. Spray the solution directly onto the clean leaves of your roses.

Basic Baking Powder spray
Mix 3 tablespoons of baking soda into 1 gallon
of water and spray the roses.

1 Tablespoon veggy oil
1 gallon unclorinated water
1 Tbsp apple cider vinegar
1 tsp brown listerine(I know this isnt organic, its what the insects dont like)
1 Tbsp liquid Soap--NOT DETERGENT. Some dish soaps say detergent in really small print somewhere on the bottle.
1 1/2 Tblsp baking soda
large spray pump.

Add vinegar at the end so it doesnt bubble over.