bleach spray

[jtjmartin]

I'll stick with the 4 oz/8.25%/gallon for a while then.

Thank you!

[jmsieglaff]

This wet and cloudy weather sucks. Despite a bleach spray treatment, nearly overnight I've had an explosion of gray leaf spot. I'll be removing leaves and hitting the plants with copper spray today. Some days of sunshine would sure helps things a great deal too.

[b54red]

Originally Posted by jmsieglaff

This wet and cloudy weather sucks. Despite a bleach spray treatment, nearly overnight I've had an explosion of gray leaf spot. I'll be removing leaves and hitting the plants with copper spray today. Some days of sunshine would sure helps things a great deal too.

If you are fighting gray mold in wet and cloudy conditions it is a very hard thing to do. It requires more treatments more often. If you have let the gray mold get too far advanced there is actually no way to stop it completely. I have only lost one plant to gray mold in the past 5 years though I have had well over a hundred get gray mold during that time. During a season I will usually plant between 20 and 40 black tomatoes some of which are very susceptible to gray mold and almost all of them get infected by it to one degree or another.

I have found that there are a couple of steps that will insure success in fighting gray mold. The first is recognizing it immediately when it first shows up on a plant and treating that plant and all near it with the bleach spray that very evening. I take it a step further and spray all my tomatoes, squash, melons and cucumbers as soon as I see the first sign of it showing up. I then follow up with a copper spray and remove the shriveled limbs and leaves caused by the bleach spray within 36 to 48 hours of the initial spraying. I then watch the plants closely for the slightest sign that it is returning and if I see a sign of it I repeat the process again. Second thing is to keep the plants sprayed with a fungicide from plant out and keep using the fungicide to help prevent the start of gray mold. The third thing is to keep the plants pruned to allow better air flow and sunlight which under normal circumstances will reduce the incidence of gray mold. Finally if we are having an extended rainy period of over 3 or 4 days I will go out and spray the plants with the diluted bleach spray in between showers every two days or so depending on the rain. I also use a slightly stronger solution than I recommend if the plants are going to be wet when they are sprayed.

I cannot stress enough how important it is to react quickly to gray mold in order to stop it. Whatever amount of gray mold you can see with the naked eye there is a whole lot more of it on the plant. The symptoms you see are usually just like the tip of an ice berg. Once the symptoms get half way up the plant then there is very little uninfected foliage left on the plant and if it is still possible to stop it there will be very little foliage left. I check my plants daily for any sign of gray mold because unlike Early Blight just removing a few leaves will not help.

Bill

[tryno12]

Thanks for the info/tutorial - much appreciated! I did the 4oz dilution last night after a couple days rain as a precaution. What exactly does blue mold look like and what fungicide do you use?
Thanks
Pete

[jmsieglaff]

Really appreciate your post Bill. This doesn't look like my typical Septoria problem, based on online poking I believe it is gray leaf spot--which is different than gray mold or no? I'm removing bad leaves now and will spray this evening. Think bleach or copper?

[jmsieglaff]

I'm now wondering if I sprayed bleach at too strong of a rate a couple days ago. I measure carefully and used 8.25%, but see spinach near the tomato plants with leaf damage that received collateral spray.

[b54red]

Originally Posted by tryno12

Thanks for the info/tutorial - much appreciated! I did the 4oz dilution last night after a couple days rain as a precaution. What exactly does blue mold look like and what fungicide do you use?
Thanks
Pete

Pete it is called Gray mold. Usually the first indication will be one or two leaves deep in the shady portion lower on the plant that will look like they are wilting or even wet and drooped like boiling water was poured on them. It will also appear as gray to tan fuzzy looking spots on the leaves. When it is really bad it will affect the fruit with soft gray spots that rot the fruit and also have lesions on the stems like Late Blight but not as severe looking.

For me copper spray works better than Daconil for warding off Gray mold and it will even stop it if it is a very mild case sometimes. Copper in a stronger mix will sure give you some plant stunting on tomatoes so I prefer keeping to the lowest recommended rates and using it as a preventative rather than as a curative. When the gray mold shows up and it usually shows up on black tomatoes like JD's Special C Tex, Black Krim, Indian Stripe, Black from Tula and others that are similar. It is also deadly to some of the Green When Ripe tomatoes that I have grown in the past. It isn't usually a problem down here on most of the reds, pinks and golds unless they are right next to a black tomato that has a severe infection; but it may act differently in your climate.

Once you suspect you have Gray mold then the best course of action is to use the diluted bleach spray as described in the thread below. Read it carefully and make sure you understand how to mix it, apply it and when to apply it. Then use a copper spray after removing the dead and shriveling diseased leaves after the bleach has worked on the at least over night. I prefer to remove the diseased leaves after about 36 hours to give them time to shrivel up from the bleach spray.

http://tomatoville.com/showthread.ph...t=bleach+spray

Bill

[b54red]

Originally Posted by jmsieglaff

Really appreciate your post Bill. This doesn't look like my typical Septoria problem, based on online poking I believe it is gray leaf spot--which is different than gray mold or no? I'm removing bad leaves now and will spray this evening. Think bleach or copper?

I usually go with copper on any kind of speck or spot disease. That looks pretty severe so I hope it is only on some of the leaves.

I would probably spray the plants with the diluted bleach spray making sure to get the undersides of the leaves as well as all the stems and the mulch under the plant and then followup with a copper spray the next day. You might want to try it on just one plant to see how it reacts first. Sometimes with some diseases and problems or with badly damaged leaves the bleach spray will kill back all the affected leaves.

I used an alternating bleach and copper spray one time in August when I had a severe case of Septoria and it finally got rid of it but I lost a lot of foliage. But since we still had a couple of months most of them recovered for fall production.

Before using the bleach spray please read carefully the whole thread on its' use.

Bill

[b54red]

Originally Posted by jmsieglaff

I'm now wondering if I sprayed bleach at too strong of a rate a couple days ago. I measure carefully and used 8.25%, but see spinach near the tomato plants with leaf damage that received collateral spray.

I have to admit I have never sprayed the diluted bleach spray on spinach or anything like it so I have no idea if it would damage it. I wouldn't think it would unless it was mixed too strong or sprayed in the sunshine.

I generally start out with 4.5 oz to a gallon if I don't see any significant problem and if I do see a disease like Gray Mold I will use the 5 to 5.25 oz to the gallon. I have not had any damage to healthy leaves on any plants when it is applied near sundown or very very early in the morning. I did have some damage when I got a bottle of no name bleach that was significantly stronger than what was stated on the label or it had something else in it that caused the damage. Since then I have stuck with the Clorox brand but I always spray a small area first when I open a new bottle just to be sure.

Bill

[jmsieglaff]

I should add the burned edges aren't pictured here. Or at least what I think was that. My only deviation was a different brand of bleach. I pruned aggressively and treated with copper tonight. Fingers crossed.

[jmsieglaff]

And that picture was the worst leaf of all my plants. The crazy thing was how suddenly it appeared as I carefully check the plants daily, although I didn't on Saturday since I wasn't home until after dark. Again fingers cross between the leaf spot and the burning. I need to get some Cholrox brand bleach.

[b54red]

The copper spary will probably keep it under control especially if you have trimmed all the sick looking stuff off. Sometimes it takes several treatments to slow or stop many of those speck and spot diseases. They are very persistent in my experience. I had a bad one on my bell peppers one year and it took a couple of months before it stopped showing up on the leaves and peppers. I think the best offense with those type diseases is a good defense. By that I mean keep regularly using fungicides that help prevent them. Of course rainy weather can throw that strategy out the window sometimes.

Bill

[jmsieglaff]

Originally Posted by b54red

The copper spary will probably keep it under control especially if you have trimmed all the sick looking stuff off. Sometimes it takes several treatments to slow or stop many of those speck and spot diseases. They are very persistent in my experience. I had a bad one on my bell peppers one year and it took a couple of months before it stopped showing up on the leaves and peppers. I think the best offense with those type diseases is a good defense. By that I mean keep regularly using fungicides that help prevent them. Of course rainy weather can throw that strategy out the window sometimes.

Bill

Thanks Bill,

I went out and peeked this morning. The plants are looking pretty good this AM, even if they are scraggly from much foliage being removed, except for the newest. The first plants will be opening flowers this week--a good week behind last year. Sunshine and breezy conditions the next few days should be good for them. Scattered afternoon showers/isolated storms are forecast, hopefully we can dodge those. I do really think some days of sunshine will help too.

If we get any rain the next few days I'll reapply copper. Typically I don't have leaf issues until mid/late June--but the cool, damp, cloudy weather must have taken its toll.

[tryno12]

Thanks a lot for all your time work to educate us on how to deal with deceases the correct way!
Pete

[jmsieglaff]

Bill,

The plants are now doing great. Some burn along leaf edge but not too bad. I will use only cholorox from now on. After pruning and spraying with copper, along with a stretch of sunny and warmer days (and dodging showers/storms Monday Tuesday), the plants are growing well and no return of any leaf spots.

Justin