Re: Tomato blight.... Has anyone used Daconil fungicide?

[femmocrat]

I read that chlorothalonil is the best ingredient to use for tomato blight. I found Daconil at the garden center. Does anyone have any experience with it? Any tips for using it, such as best time of day, weather conditions, etc.

I have to reapply it every 7 days. I have spent the past 3 mornings crawling around trying to remove any leaf that had the symptoms (yellowish with dark spots). I am so afraid of losing the tomato crop that I decided to cross over to the dark side and plan a chemical attack. The rest of my garden is still organic!

I planted 18 tomato plants, most of which were heirloom varieties that I got at an extension-service garden fair. They have been saying that "Bonnie"-brand plants were the culprits; if so, it has spread to all of my tomatoes. :cry: The only Bonnies I bought were a couple of yellow cherry tomatoes that I couldn't find anywhere else. Damn.

[CC]

1. I would say just follow the directions

on the Daconil. That would be the best source on proper use. Our local extension service is telling us to pull out and double bag any plants we have that have late blight. Supposedly once you see it it is too late to stop it so they are suggesting you use a preventive fungicide. Also that you water from the roots and try to avoid getting water on the plants leaves etc. Good luck and sending vibes your way for healthy tomatoes.

[femmocrat]

2. Thank you. I can't bear to throw away the plants... yet.

I know I should have used a preventative, but have never had this problem before. The cool wet weather didn't help either. I could just cry.

Thanks for the vibes and the good information.

[CC]

3. I have 32 heirloom tomato

plants outside now, and am paranoid after the county sent out news of this. I could sit down and cry with you because I know it would devastate me. There is a local organic heirloom tomato (over veggies too) grower just about in melt down worrying about it. I will not risk their livelihood if my tomatoes get it. Would hate to have them hit with it even more. :hug:

[amerikat]

4. I'm having the same problem on some of my tomato plants.

I don't want any bad chems in the garden. The garden center I went to
had an organic product called copper soap fungicide. I sprayed yesterday
then it rained like hell. I'll apply more tomorrow and let you know how it works.

http://www.saferbrand.com/store/garden-care/98932

On edit: I guess you live in the northeast? Very common problem here
due to all the rain we have had in the last 5 weeks and the cool temps too.

Good luck, I'll keep you posted on my results with this product.

[flying_wahini]

5. Liquid copper ?

see my post on Lilacs...

[bvar22]

6. Don't know f the Daconil will help.

These are some of the things we are doing to limit Late Blight and other fungal problems:

Late Blight of Tomatoes is a problem here.
In Central Arkansas, we have HIGH humidity with dripping dew every morning, and have experienced "Late Blight" in our tomatoes, as well as fungal and mold problems with other crops.

For tomatoes we did several things this year that have had "some" beneficial effects:

1) Instead of planting tomatoes together in a clump, we spread the tomato plants throughout the garden reducing transmission from plant to plant.

2) The infections seem to occur initially on branches that are near the ground, or especially touching the ground. We have pruned low branches and encouraged the plants to grow UP instead of out. This also encourages more air circulation. We were somewhat experimental this year, but will do this aggressively next year.

3) We immediately prune off any branches that show brown or yellow spots and remove them from the garden area. The host plant is already infected, but this seems to slow the progression, and may impede the spread to other plants.

4) Last year, I tried to nurse along infected plants with little results.
The tomatoes harvested from these weak plants were disappointing.
This year, we have started some seedlings for a "late" planting in a bed that has had no tomatoes this year. Our new approach will be to pull them up, get them out of the garden, plant new seedings in a different bed, and hope for a late frost.

5) We no longer compost ANY plant that has shown any symptoms of fungus or disease. This differs from the linked article, but we believe that the safety factor more than outweighs the limited benefits of a few plants added to the compost.

6) Heavy Mulching
I have read that most fungal infections originate in the soil. It also seems that this year, the blight we experienced first occurred on leaves that had been splashed with soil from a heavy rain.


This is just anecdotal testimony, but we have had fungal problems with other plants, most notably cucumbers and cantaloupes. This year, we planted cantaloupes, and added a layer of newspapers topped with a heavy layer of hardwood mulch. The cantaloupe plants have almost no contact with bare earth.

A stout trellis was added later, and the vines were kept off the ground.
We have had a great year for cantaloupes. Unlike last year, we have healthy, strong, green, unblighted plants going strong into August.
Best tasting cantaloupes ever.

Next year, we will use this method with out tomatoes.
We are going to cover the bare earth with newspapers, and plant the seedling through a small hole in the newspaper, then cover with a straw mulch.

All of the information in this post is purely personal experience specific to our garden.
Your mileage could vary.

Good luck with your battle.

[flying_wahini]

7. Rather than Bonnie - which I got and had disease, too

I think it was Hurrican Ike that watered down all the local mulch pits and all the thousands of

water logged brush that they picked up and later used for mulch.

Of course, I live in Houston area, great area for mildew anyway.

[bvar22]

8. Probably not a good idea to save seeds from blighted plants.

Control
Reduce the amount of initial inoculum or suppress the rate of disease development. Start by avoiding seeds from affected fruit. Commercial tomato seed will not harbor P. infestans because acid and fermentation treatments of the seed destroy the fungus. Use diseasefree seedlings.

Remove and destroy blighted tomato or potato plants. Eliminate all tomato or potato cull piles in the vicinity of the tomato field. Reduce leaf wetness by staking tomatoes and using drip irrigation. If drip irrigation is not available, reduce the number of furrow irrigations to a minimum or use sprinkler irrigation in the morning or midday to prevent the foliage from being wet overnight. Avoid overfertilization of nitrogen.

Spores of P. infestans can be dispersed aerially over long distances; therefore, all tomato growers nearby in the production region need to collaborate to eliminate sources of inoculum. If this doesn’t happen, a few fields with infected plants can affect production over a much larger region.

http://www.avrdc.org/pdf/tomato/late_blight.pdf

I remember reading online about a way to inoculate tomato seeds against diseases, but am unable to find it now.

Definitely do NOT compost blighted plants, and remove all plant debris from the garden in the Fall.

[femmocrat]

9. Update! And a question.....

Well, I did use the Daconil every week, but the fungus still got most of the leaves. However, I am having a bumper crop of tomatoes! We actually have toooo many.

They say the fungus won't survive the winter, but to be certain, I will plant tomatoes in a different bed next year. I knew not to compost the plants or save the seeds. Dead leaves went into plastic bags then into the trash, and that is how I will dispose of the plants. And next year I will apply the fungicide as soon as I plant in May.

BTW, I found this recipe for tomato blight online somewhere. Has anyone ever used it?

1 gal. water
2 Tbsp. baking soda
1 Tbsp. epsom salts
2 Tbsp. lemon dish soap.

Mix together and spray on tomato plants.