Should I start spraying???

[markd42]

Hello All, I have about 55 plants that were all doing well, but i seem to be now plagued with septoria, or some kind of blight. Ive NEVER had to spary before but it seems I may have to. I removed all diseased leaves a week or so ago and now more infection is appearing. See photos. SOme varieties are more affected than others; my isis candy plants and italian heirlooms have been pretty badly beaten up. I have access to the Fungonil concentrate; I believe it makes one gallon of spray, yet others have indicated to use only 1T per gallon. PLease clarify. Do you have any idea of how many gallons I would need to treat 50 plants? What are the implications of using a fungicide? I assume my kids and I will no longer be able to eat right from the vine and washing the fruit becomes very important? I definitely late with this decision but I figure better late than never. My plants have been in the ground since May 21 so they are full of fruit. I hate to lose them all now. Please help. A few shots of Blondekopfchen and Jaunne Flamme for your entertainment as well. Best regards to you all.

Mark
Westchester County NY

[RayR]

As far as I can see from the pictures, it looks like you have both Septoria and Early Blight which is not unusual since I rarely see one without the other when they show up in my own garden here on the other side of NY.
Bonide Fung-onil is a chlorothanil fungicide like Daconil. One gallon of mix is likely not enough for 55 plants and you have to do repeat applications and it washes off in the rain. It is not a cure for the fungal infections, but it is a preventative to slow the spread. You did the right thing pruning the infected leaves ( dispose of them in the trash, don't leave them on your property), but you can bet your life that the leaves that do not show lesions or yellowing yet already have or will have spores on them, which is where a preventative fungicide is helpful.
A copper soap fungicide is an alternative, I used Soap Shield shield last year which is sold by Gardens Alive!, it worked well at slowing the spread of the diseases and it had the added benefit that it didn't wash off in the rain easily at all. Any way you go with any fungicide will require repeat applications to be effective.

[b54red]

It must really be something not to have to spray. My plants only look disease free for a few weeks in the early spring before the humidity starts getting high and then it is off to the races to see whether the tomatoes or the diseases will win. The diseases usually win in the long run but sometimes the tomatoes finish first.

[creister]

b54,

I would estimate at least 3-4 gallons for that many plants. This year, I used 2 gallons on 22 plants. I laid it on thick, but when plants were full of leaves, that was just about right. I may have had to use 2.5 a few times when I did the squash. I would guess 4 would be a starting point.

Do you use a hose end or pump up sprayer? I've found I use more pesticide when using a hose end sprayer than a pump up sprayer. I do like the hose end, seems quicker and more convenient and I think I get better overall coverage on the plants.

[bcday]

The plant in pic #6 looks like it has the type of foliage that is called wispy/droopy. Although I can see a few curled-up leaves that may be the result of some environmental stress, varieties with the wispy/droopy foliage type always look like they need water. But it's just the way they naturally grow. If you can post the name of the variety in that pic we might be able to tell you if it should have wispy/droopy foliage.

In pic #7 the circular spot on one side of the top fruit in the truss looks like a stinkbug bite. It's unpleasant but it's not a disease.

The leaves in pics #3 and #4, and a couple of the leaves near the green fruit cluster in pic #8 do look like they have Septoria. I think it's a good idea to start spraying with the antifungal of your choice and continue removing any leaves that show Septoria spots. Keep in mind that it takes a few days for these spots to appear after the leaf becomes infected. Fungonil is only a preventative and will not kill any Septoria that is already growing, so even after you start spraying spots will continue to appear where there was Septoria infection that wasn't visible earlier. Even with spraying, Septoria can be difficult to control.

Read the label carefully on the bottle of Fungonil concentrate. The label on mine clearly says to mix one tablespoon of concentrate in one gallon of water for tomatoes and that's what I do. I don't eat the fruit right off the vines if plants have been sprayed. But if you don't spray, your tomato season is likely to be very much shortened. Septoria can cause the plants to drop most of their foliage, and what fruit you get may be stunted or have sun scald because of the loss of foliage.

Try not to touch healthy foliage in the process of removing diseased leaves, which would spread the disease. Seal the diseased foliage in a plastic bag for disposal in the household trash, not in your compost pile. Also avoid wetting the foliage while watering the plants and don't work among the plants while they are wet from rain or dew. Septoria spots can also appear on stems. Whether to remove those stems is a judgment call depending on such things as whether there are flowers and/or fruit on that branch, how badly infected the stem is, and whether removing it would allow better air circulation so that wet foliage could dry faster. Wet foliage and humid conditions encourage Septoria and other foliar fungal diseases. Doing what you can to keep foliage dry and humidity down along with removing diseased leaves before they can release Septoria spores into the air will help to keep the plants healthy.

[markd42]

Dear bcday, Yes, the plant in that pic is italian heirloom which is kind of an oxheart type and indeed has droopy leaves. Bought the fungonil and spray tank today. Its going to be in the 90'S all week so I guess I'll wait till tomorrow late afternoon to apply. Thanks for the insights.

[b54red]

I bit the bullet early this year and bought a very expensive backpack sprayer from Northern Tool with the brand name of SP. Since I have gone through so many pump sprayers and found the better ones so much easier to use I did some research and picked one that I thought would be easier to use. The one I bought will build up pressure greater than 150 psi and has a good heavy brass wand with a very good adjustable tip. After using it only a couple of times I realized what a fool I was not to have gotten one sooner. I am able to mix up to 4 gallons in one spray tank and with the very high pressure spray it is so much easier to get good coverage. It is also much less physically demanding to keep it pumped up. The high pressure fine mist it puts out means that I need far less spray than in the past and I can complete my spraying in less than half the time of a conventional pump sprayer.

[markd42]

I hear you b54. I sprayed last night for the first time and it took me a good hour and change to spray all 50 plants; went thorough about 8 gallons of Fungo-nil using a wimpy 2.5 gallon sprayer. Hopefully this was the first step in putting a halt to further foliage loss due to fungal diseases. My plants are loaded with fruit and even a few varieties are starting to ripen up. Will keep the board posted regarding teh effectiveness of the spraying. Maybe next year I will step up and get a better sprayer.

Mark

[amideutch]

Bonide Fung-onil is a chlorothanil fungicide like Daconil

As stated before Fungo-nil aka Daconil is a preventative and not a curative. Once the plants are infected Fungo-nil will not help. Either use a copper based product as previously mentioned or Exel-LG and Actinovate which are both Bio-Friendly to eradicate the disease. Exel-LG is also a systemic which will be absorbed by the plant and fight the bad guys from within. Ami

[enchantelope]

I thought Exel-LG and Actinovate were also preventatives and that there are no curatives for fungal diseases.?

[b54red]

The only true "cure" for fungal diseases I have found is the dilute bleach spray. It works well on most diseases and causes the infected leaves to dry up and die. It has no preventative effect other than killing most of the spores present on the plant at the time of the spraying. I use it fairly often if rains are frequent or diseases are popping up despite the use of Daconil. I try to apply Daconil a few hours later or the next day after using the bleach spray to help prevent new infections.

Mark, eight gallons of spray for only 50 plants seems like a lot. I would only need about 2 gallons for 50 plants unless they were all over 6 feet tall and then it would only take about 3 gallons. You could save yourself some spraying and mixing by keeping the sprayer pumped up to maximum pressure and using a finer mist.

[RayR]

Originally Posted by enchantelope

I thought Exel-LG and Actinovate were also preventatives and that there are no curatives for fungal diseases.?

Not entirely correct but nothing used as a fungicide is has the same effect on all species of pathogens. Phosphorous acid compounds, particularly Potassium Salts of Phosphorous Acids like in Excel-LG do have a direct curative effect on many oomycetes pathogens, but not all. It may not have that direct effect on true fungal pathogens like Septoria or Early Blight, but it's indirect effect as a preventative by triggering Systemic Acquired Resistance in the plant may contribute to controlling disease spread.

"Phosphorous acid has both direct and indirect effects on oomycetes. It directly inhibits a particular process (oxidative phosphorylation) in the metabolism of oomycetes (McGrath 2004). An indirect effect is the stimulation of the plant's natural defense response against pathogen attack (Biagro Western Sales, Inc. 2003; Smillie, Grant, and Guest 1989)."

With bio-fungicides like Actinovate, you are applying living beneficial bacteria to colonize the leaves and stems of the plant. These bacteria a natural enemies of fungal pathogens. Bacteria don't have mouths or sharp teeth, but they have adapted to surviving by excreting compounds that are damaging to competitors by breaking down their cell walls. I guess in that regard they are both a preventative and a curative since they can effectively kill many types of fungal spores.

[amideutch]

RayR, excellent answer and explanation. Ami

[Lorri D]

b54red, can you tell me what ratio you use with your bleach spray? I think I want to try that next. We get blight and this year we've had a lot more rain than usual in the summer time and the blight keeps coming back. The other sprays are getting very expensive to keep using (I also have a lot of plants). I tried baking soda, but I think it was a little less effective than I'd like.

[b54red]

The bleach spray solution that I use is the result of much experimenting to find the most effective ratio to kill back fungus and disease without doing undue damage to the plants. It is important to spray very early or very late in the day to prevent leaf burn from the sun hitting the solution on the leaves. To get the maximum number of disease spores you need to use a fine mist and hit all surfaces of the plant and I like to spray the ground or mulch under the plant with the fine mist. It is also important to remember that this is to kill back disease not to prevent disease. The bleach oxidizes very quickly after being sprayed and has no residual preventative action so it is important to apply a fungicide the next day for prevention. I sometimes reapply a day or two later to make sure I got all of the areas affected by disease or if it is an especially difficult disease to control like Septoria. Unlike fungicides it can be used as often as you like and you don't have to wait to harvest after spraying. By the time you rinse your sprayer and pick any fruit the solution is already neutralized by oxidation.

The mix I use is take a full gallon of water and add 8 ounces of regular strength bleach (I prefer regular Clorox for its consistency) and a few drops of plain dish washing soap for a spreader sticker. After spraying thoroughly rinse your sprayer because the bleach is highly reactive. Never mix any other chemicals in the solution because they may react with the bleach. Don't try to store the solution as it will breakdown rather fast and become less effective. It is cheap enough to mix fresh every time. It is easy enough to make a smaller batch by keeping the proportions the same.

Withing a few days after spraying diseased leaves will start drying up and dying while the healthy growth will be unaffected. It is important not to allow a disease to infect most of the plant before you use it because it will kill most if not all of the diseased leaves. Usually the extent of infection is much greater than is visible with the naked eye so once a disease starts up despite the use of fungicides it is best to spray as soon as possible to prevent the spread then reapply a fungicide.

If you have doubts about using it just try it on a plant or two and see the results. You may be surprised by the extent of the infection which the spray will make clear. Do not use a much stronger solution or spray in the midday sun.