Black spot is a fungus. "Antibacterial soap" could be considered an anti biotic. Generally, they're not effective against fungi. It is POSSIBLE, using Insecticidal Soap MAY have a beneficial effect on black spot because it is fat, an oil which remains solid at room temperature. Oil coats the leaf surfaces and can help prevent fungi spores from germinating on them as long as they fall on the oil coating. Horticultural oil can smother mildew and insects. Insecticidal Soap dries out the insects exoskeleton, so they can't molt and strangle in their own skins.

Use of this type of soap may help with some fungal outbreaks, and perhaps some insect issues, but it wouldn't be due to the antibacterial elements involved. The surfactants (like a spreader-sticker) and water ingredients would be far more likely to be what worked. Oils are frequently used as surfactants, and there are horticultural oils officially licensed for your desired use.

I wouldn't suggest using antibacterial soap for anything other than what it is appropriately labeled for...washing your hands. Though a very mild anti biotic, it is produced and sold to cleanse your hands, dishes and body. Over use, misuse, inappropriate use of any chemical can have far more damaging results than benefits. Keep your antibiotics for killing bacteria where they're supposed to be used. Use insecticides and fungicides for killing fungi and bugs. Kim

is it okay if i get the antibacterial soap on buds and new growth?

Bacteria on the foliage actually help to control fungus diseases. I don't know whether antibacterial soap will harm foliage or not, but I doubt it will help with blackspot--could make it worse. Safer's Insecticidal Soap is effective for aphids and worms if sprayed directly on the pest. Reportedly, it can burn foliage in hot weather. It doesn't control fungus diseases.

If you have applied antibacterial soap, I'd recommend rinsing it off.

Dish Soap Solution for Black Spot

Any old antibacterial dish soap will work fine. I use Ajax anti-bacterial because that is my household dish soap and it has worked wonders. Simply combine � cup anti-bacterial dish soap in a 2 liter bottle, mix well and use a spray bottle to apply to the rose bush. I usually just take the spray off of an old Windex bottle, rinse it out well, and connect it to the top of the 2 liter bottle. Label it and leave it in the green house (great way to recycle). Apply every 5-7 days until Black Spot is eliminated and then once every 2 weeks to prevent future breakouts.

i got all this information from a website

Vinegar and Water Black Spot Solution

Add 3 tables spoons of Apple Cider Vinegar to a gallon of water. Pour into a spray bottle and spray your roses evenly. Be sure to spray the tops and bottoms of the leaves, stems and canes. Also, spray the soil near the plant to kill any Black Spot fungus that may be lingering in the soil from previous dead leaves or water applications. Spray in the early morning once a week until the Black Spot is eliminated then spray every 2 weeks to prevent a future breakout of Black Spot. (Adding one table spoon of Molasses will help the application by helping the vinegar to stick to the leaves. It is not necessary but can be very helpful.)

Baking Soda Black Spot Treatment Solution

To treat Black Spot on roses, the baking soda solution also works very well. Simply combine, 4 tablespoons of baking soda, one tablespoon of Molasses and one gallon of water. Mix well and spray thoroughly on roses that have been infected with Black Spot. Reapply once a week until cured. Then apply every few weeks to prevent future reoccurrences.

Treating Black Spot isn't that hard if properly done. Using in of the above solutions will work if applied thoroughly and as often as once a week while treating and every 2 weeks to prevent Black Spot. It is always a good idea to spray all of your rose bushes and not just the ones that are showing signs of Black Spot. This will help to insure that the fungus has been cured fully instead of curing one plant just to find out that another rose had it and now you are dealing with it all over again trying to fight the same battle.

Here is a link that might be useful: http://voices.yahoo.com/how-treat-black-spots-roses-1823860.html

I can pick on several issues I have with the article you linked. However, here is the relevant question: Where does the author live? Can't tell from the article or the profile. If the author lives in an area with low humidity, then perhaps these treatments work for her. I don't live in an area with low humidity, these treatments do not work for me. And, I would NEVER use vinegar on my leaves. We don't know what varieties of roses she grows. The article is now 4 years old, I wonder if she's having the same results.

I'll concur with the input from Kim Rupert and michaelg.

Not everything you read on the Internet is true.

There are people who believe that Elvis is alive, and there are whole bulletin boards "documenting" sightings of "The King," in 2012.

The fact that there are articles attesting to this does not make it true.

Jeri

No no no! That article is a bunch of crap.

If you follow that baking soda recipe it will ruin your plants. Somebody in the game of internet "Telephone" has confused teaspoons with tablespoons. There is a somewhat effective recipe that calls for 1 TB baking soda and 2-1/2 TB horticultural spray oil. This will control powdery mildew (if that is a problem) and slow down the blackspot if your conditions are not severe. The soda/oil mixture can burn plants in hot weather. It is better to substitute equally safe potassium bicarbonate for baking soda. Potassium bicarbonate fungicide can be found at a good garden center (Remedy, etc.).

Vinegar is a general herbicide that will kill plants in sufficient concentration. I don't know whether 3 TB/gal is safe or not, but I'm certain it will not control blackspot if you have substantial disease pressure.

You asked if there were any bad side effects to using this stuff. Main one being, it's unlikely to work, unless you live some place like California or Arizona where there isn't much blackspot to start with. In which case it isn't actually working anyway - there's nothing to get rid of, you're just using it AND you happen to have no blackspot. No cause/effect relationship.

The other bad side effect being that you're encouraging disease-causing bacteria to evolve to be resistant to antibiotics when you over-use antibacterial soaps. Doctors and public health officials actually recommend against routinely using antibacterial soap for that reason - our antibiotics are becoming useless for treating diseases.

FYI, there is no cure for blackspot. Any recipe promising a cure is a hoax. And I've tried various soap and baking soda recipes on preventing blackspot - they don't work. They help with preventing botrytis and powdery mildew a little, but not blackspot.

The following may be useful:

Evaluating Natural Products for Control of Black
Spot Disease on Roses

Here is a link that might be useful: Evaluating Natural Products for Control of Black

LOL.

Antibacterial soap isn't good for anything at all!!! It's one of those bad ideas that has caught on in our germ-phobic culture and does nothing at all except make germs morph into stronger more resistant germs.

"I've tried various soap and baking soda recipes on preventing blackspot - they don't work. They help with preventing botrytis and powdery mildew a little, but not blackspot."

*** MOREOVER -- They can be very tricky to use, even IF it's mildew you're dealing with. I know people who have ruined an entire rose garden's foliage, in that attempt, because they didn't get it just right. It's a fool's game.

Jeri

what if at the begining of spring i pull off all the leaves that are near the soil close to the ground since black spot comes from the ground up if i dont let the plant grow leaves close to the soil black spot will not be able to get to the plant UNLESS black spot can somehow climb the stems and then get to the leaves

everytime i get black spot it gets to the bottom leaves first then it makes its way up AND this year the only rose plant that doesnt have black spot is the one that doesnt have any leaves growing on the bottem 6 inches of the plant i didnt pull the leaves off they just didnt grow maybe it had something to do with last falls black spots

Hrose--if you are growing HTs and such, and if you prune severely in spring, then removing the lowest leaves will slow the onset of blackspot. If you are growing shrub roses or other hardy roses that are not pruned severely, then it won't help. The reason is that blackspot carries over winter in spots on the green canes, from which it spreads to the leaves. It can also carry over in fallen leaves if there are no green canes surviving.

Removing the lower leaves can gain you a few weeks but it won't keep the disease from taking hold for the season.

"black spot comes from the ground up" ???

I'm not sure that is a universally true statement. I thought blackspot had more to do with weather conditions--the bs responding to certain temperatures (70s and 80s? I never remember exactly what range of temps.)

Besides, lots of gardeners complain when their roses go around with bare ankles.

You really have 3 basic choices:
1. Buy only very disease-resistant roses
2. If the BS attack is not too strong and devastating, learn to live with it.
3. If you can't stand the BS, no matter how much or how little, spray with a good fungicide. I spray some of my roses (but not all of them since quite a few are very disease-resistant and don't get much BS at all) 2-3 times in the spring and a couple times in the fall. Mid-summer is so hot that I usually don't need to worry about BS--too hot even for BS!

The simple truth is, if you grow roses, they will get BS--some just in passing but others nearly destroyed by it.

Unless you live in California which, for some unfair reason, doesn't seem to have much BS--perhaps almost none at all. Truly a geographically unfair situation.

Kate

do blackspots germinate in hot dry weather or cool wet weather of hot humid weather?

yeah i was reading somewhere that germs in the soil splash onto the leaves resulting in black spot explanies why the leaves lower leaves catch it first

antibacterial soap kills the germs am i the only one making the connection here?

Plants don't have germs.

I live in northern Ohio. I do not spray anything (except in rare experiments). I do not exhibit so I can tolerate inperfect leaves. I have almost no blackspot until late in the fall. I look at blackspot then as part of nature's way of preparing the roses to survive the winter.

Plants have immune systems. An active present research area is how to optimize the plant immune system. A 2007 paper on this subject concerning blackspot on roses is at:
http://www.tandfonline.com/doi/abs/10.1080/17429140701701071
Notice the word "biocontrol". Another subarea under the general term biocontrol is to allow the friendly fungi to reach equilibrium with the blackspot. The following may be useful in putting this area of biocontrol into layman terms:

"Disease-suppressive soil microorganisms have been found in many places. In monoculture wheat the severity of "take all" disease often decreases within three to five years. This phenomenon is known as "take all decline," and is considered an effective natural control. Although the mechanisms are not completely understood, the decline is associated with changes in soil microorganisms that compete with and prey on the fungus. Melon plants grown in the Chateaurenard region of France do not show Fusarium wilt symptoms even though the fungus is present in the soil. Soils with suppressive characteristics tend to develop slowly and are usually found in fields where perennial crops or monocultures have been grown for many years.
Suppressiveness may be lost if the monoculture is interrupted even for one year, or if pesticides are applied. For example, researchers first recognized soils suppressive to cereal-cyst nematode when nematode numbers increased after application of a broad-spectrum biocide. Many species of fungi and bacteria in the genera Trichoderma, Streptomyces, Bacillus and Pseudomonas suppress diseases, but at this time only a few strains are commercially available. Additional commercial products may be available soon, however, as this is currently an active research area."

The quote was taken from:

http://140.254.84.215/cached.jsp?idx=0amp;id=151762

Here is a link that might be useful: friendly fungi equilibrium

Hrose, BS is fungus, not bacteria. So bactericidal soap is not an answer.You need something that kills fungus (fungicide) or you need to grow resistant roses. We don't know where you garden. If you tell what is your state, we can give you more meaningful advice on what could be the best practice in your climate.
Olga

Text of the Lecture�Canadian Rose Society Silver Jubilee celebrations, July 2005

Chemical Vs. Biological Controls for Diseases
Dr. Lakshmi Sridharan

Here is a link that might be useful: Chemical Vs. Biological Controls for Diseases

Both vinegar and soap (even the anti-bacterial kind) have been mixed in with my rose sprays on a regular basis in the past.

HOWEVER - this is in very, very small amounts to set the PH of the mixture (the vinegar) and to provide a sticker/spreader to the solution (the soap).

If you can find it, you're still better off using Indicate 5 to do this. ;-)

And it has nothing to do as an anti-fungus or pesticide formulation. Those chemicals were already in the mix and the PH correction and spreader/sticker help the chemicals perform better on the roses.

i think the soap is burning the leaves a little bit its showing today it was sunny all day and now i can see little burnt spots

i think i may have added too much soap into the mix

Germs don't cause blackspot, blackspot fungus spores cause blackspot. Keep in mind, If all or any of those remedies really worked, we'd all be using them as we're continuously looking for the perfect effective blackspot control.
You asked "Am i the only one making the connection here?"
Guess so, but you should make sure there is a connection to make before you question years of combined experience.

I'm not so sure but what this person is a put-on . . .

Jeri

whats do you mean Jeri??

more bad news i was watering the rose today and it looked like the roses were taking a bubble bath :( :( from all the soap mix i applied the other day is it possible the soap might get to the root system and cause serious damage to the plant? i hope not and this dame soap mix burnt enough of my leaves i took a closer look and there are a lot of burnt leaves i wish i had never sprayed them

from now on i';m just gonna do what Katie does spray with a good fungicide "2-3 times in the spring and a couple times in the fall."

whats do you mean Jeri??

more bad news i was watering the rose's today and it looked like the roses were taking a bubble bath :( :( from all the soap mix i applied the other day is it possible the soap might get to the root system and cause serious damage to the plant? i hope not and this dame soap mix burnt enough of my leaves i took a closer look and there are a lot of burnt leaves i wish i had never sprayed them!

from now on i';m just gonna do what Katie does spray with a good fungicide "2-3 times in the spring and a couple times in the fall."

I live in Canada Ontario Zone 5A i get hit with black spots during spring and fall for anyone that wants to know

on this website it says that this rose erotica hybrid tea is resistant to black spot ha! if it were i wouldnt be having this problem AND it says zone 7 to 10 i'm in zone 5a and these roses survived the winter no problem although they do have a few black/brown spots on the stems

http://d a ve s ga r de n .com/guides/pf/go/63842/#b

It has been scientifically determined there are FIVE different races of black spot in the US alone, something like fifteen different ones world wide. A rose can be resistant to one and none of the other fourteen. VERY few roses are resistant to two or more. Knock Out is the one most resistant to the most different races and even it can get black spot. Don't damn the rose for getting the fungi. Unless you deliberately collect the different types and deliberately infect your roses to check for resistance (which is exactly what Bill Radler, creator of Knock Out did) you can't know without growing them everywhere. Perhaps that rose IS resistant to the race which grows where its disease resistance was tested and perhaps YOU have a different race/strain/type. Kim

I tried my best to take the soap off the leaves and stems

I think i may have caused more damage then the black spot...