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b54red August 27, 2010 03:46 AM

Hey heirloomdaddy, did you have a little scare when you saw the newly dead foliage after the spraying? It really gave me a fright the first time I used it on sqaush with powdery mildew and I saw those big leaves shriveling up. It just seems to speed up the dying of the diseased leaves on tomatoes while slowing or stopping the spread to the healthy tissue.

RinTinTin August 28, 2010 12:44 PM

Ami: (and anyone else not living in the U.S.)

I should point out that household bleach sold in the US is usually a 5-6% solution, while in much of Europe, it is quite a bit stronger(sometimes double that). Take that into consideration before doing your dilutions, and read the label to see what solution you are using. Too much of a good thing is not a good thing.

b54red August 29, 2010 04:35 AM


Originally Posted by RinTinTin (Post 182418)
Ami: (and anyone else not living in the U.S.)

I should point out that household bleach sold in the US is usually a 5-6% solution, while in much of Europe, it is quite a bit stronger(sometimes double that). Take that into consideration before doing your dilutions, and read the label to see what solution you are using. Too much of a good thing is not a good thing.

I was not aware that the solutions were different. I figured Clorox would be the same the world over. I don't use any other brand because I worry the solution might be too weak or too strong. I've seen some cheap brands with only a little over 3% sodium hypochlorite and that is way too weak once you add it to water to do anything for your disease problems. The bleach I use is between 5% and 6% sodium hypochlorite. A little variation doesn't hurt but I try to never get my final solution too strong. It's not that hard to spray again if neccessary.

amideutch August 29, 2010 10:52 AM

Red, don't be so sure on the concentrations of Chlorox. The MSDS for Chlorox Regular Bleach shows the concentration of Sodium Hypochlorite to be 5-10%.
For the bleach carried here in Germany (Not Chlorox) available locally shows a concentration of 1-10% plus it also includes Sodium Carbonate at a concentration of 1-10%. So , all bleaches are not the same. So it would behoove anybody who is going to use bleach to check out the MSDS for the particular product they want to use. Ami

b54red August 30, 2010 04:58 PM

Ami in all the years I have been using Clorox I have only seen one version that was over 6% and that was Clorox Ultra. I'm sure they make industrial products that might be stronger; but I've never seen them on the grocery shelves.

heirloomdaddy September 7, 2010 12:58 PM

3rd spraying
I am shocked at the success and simplicity that this approach creates.

My JBT was on it's DEATH BED. it was toast, with literally 1 healthy looking sprout and all dead foliage.

It is a new plant. It is making the comeback of a lifetime!

My other plants are definitely responding very positively, much more so than when i just sprayed daconil, which i will only spray now once in a while after a bleach spray. My cucurbits are happier now too.

I imagine this works as somewhat of a pest repellent as well?

b54red September 7, 2010 04:08 PM

I'm very glad to hear the success you had with the Clorox spray. If it weren't for finding this treatment I would have stopped or severely limited my tomato growing years ago. Another great thing about it is it can be used fairly often with no bad effects and you don't have to wait to eat your produce. It has seemed to help with all non systemic foliage disease on everything I have tried it on. So far I have seen no sign of diseases building a tolerance to it. Of course nobody is making a financial killing off it so it isn't highly touted like some products that cost a great deal and do very little.
The one thing it will do is kill the entire plant if it is totally infected with disease all the way into the new growth. I recommend using it as soon as the diseases are apparent and not wait for them to spread all over the plant.
Another good thing about it is I don't find it necessary to cut off all of the affected limbs because the spray disinfects them. I have not noticed the diseases spreading any faster when I don't remove the diseased portions of the plant. Eventually the solution does that on it's own by drying them up and they will just fall off after a while. It does look better though to get rid of them if you have the time.

heirloomdaddy September 7, 2010 04:20 PM


I'm really really glad I found your initial suggestion. I was actually getting really depressed. I know that part of the beauty of this hobby of ours, is enjoying this amazing process that is bigger than ourselves, but after being reamed by this years conditions, I was very disheartened. My yield has been very bad. It's a real bummer to put so much thought, time, and passion into something just to have it fail for the most part.

Hopefully this treatment will remain as successful for me as it has been so only concern with it, is killing-off beneficials I will regularly supplement with compost tea next season, in hopes of re-introducing any friendlies that the bleach may harm. Preventative bleach sprays of lower concentration will begin long before any signs of sickness next year, and I'm no longer worried about my cucurbits!

b54red September 7, 2010 04:35 PM

I have not seen any lessening of beneficials or non-beneficials from the bleach. I probably have to use it far more than you will ever have to because of our extreme humidity and heat. I do wait til sundown to spray when there are no bees flying around. I know it doesn't bother whiteflies or spider mites which I soak every time I have sprayed lately.

b54red September 7, 2010 04:47 PM

I've been to LA a couple of times and the climate seems wonderful. Imagine what it is like trying to grow tomatoes where the temps and humidity can hover near 100 for weeks on end. Some mornings your plants are so wet from the high humidity that water is dripping off of them like right after a heavy rain. It's really hard to keep the foliage diseases at bay under those conditions and like you I became despondent about ever having a successful tomato growing season.
I was to the point where I didn't care if the treatment finished off my sickly plants or not when I first used it. Some of them did die because the plants were so thoroughly infected but the ones that survived got a new lease on life and I got a new lease on tomato growing. There are now very few days from mid June to Christmas that I can't go out and pick a fresh tomato. Now if I can just find a solution for fusarium wilt and whiteflies.

maf September 7, 2010 05:05 PM

Does this also work well in cooler weather later in the season when the plants are not growing much, not expecting any further vegetative growth, just to finish off growing and ripening the tomatoes still on the plant? It is probably 65F days and 50F nights here now. I pulled my diseased plants but I would like something in reserve to try on the others if they are hit.

TZ-OH6 September 7, 2010 05:07 PM

Another option is to use swimming pool chlorine (quat ammon chloride). It is more or less the same as Physan greenhouse disinfectant/algicide/viricide, which many use as a profilactic antifungal spray on plants.

b54red September 7, 2010 07:59 PM

maf, I don't think the temperature makes too much of a difference and since it doesn't seem to harm healthy plant growth as long as the concentration of the spray is kept below 7 or 8 % and not used in the heat of the day. Just remember 8 ounces of regular strength Clorox added to one full gallon of water. If you find a stronger or weaker version of bleach you will have to adjust accordingly. I did find using less than a 5% dilution did not have as much affect. I think the Sodium Hypochlorite concentration has to be high enough to stop the spore growth so if I were using it as a preventative I would add between 6 1/2 and 7 ounces to the water.

RinTinTin September 8, 2010 01:09 AM

Swimming pool chlorine is usually about double the chlorine content of household bleach. The swimming pool stuff is usually in the 12-17% range. Read the label before mixing!

Cole_Robbie June 14, 2015 03:03 AM

I have whiteflies in my high tunnel, and now also have the black sooty mold that is the result of the infestation. The variety that has the whiteflies and mold the worst is a Chinese dwarf called Qiyanai Huang. I sprayed it with a 1.5% peroxide solution, and a day later it looks much better, like most of the most has died.

The peroxide is too expensive. I was looking for a bleach alternative. Google led me to this old thread. I think it is worthy of a bump. I am going to try the 8 oz to 1 gal mixture to try and kill the sooty mold.

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