jimmykx250
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Posts: 38
Joined: Tue Jun 02, 2009 11:23 am
Location: Northern illinois

blight?

What do you do if you suspect you have issues with your garden soil? How do you sterlize it? I have planted tomatoes twice in the same spot in the garden and I think it's blight?!?!? I still get my harvest and at this point the bottom 1/2 of the plant looks dead but the top half is green as can be.
Same thing happened last year! I know next year I will move the tomatoes to the other end of the garden. Thanks,

TZ -OH6
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Location: Mid Ohio

Blight is not a soil problem, it is a leaf moisture problem so about all you can do is space plants properly, trim lower leaves to aid air flow, mulch to prevent spore splashup, and spray fungicides.


Soil problems are generaly wilts (fusarium, Verticilium etc) or nematodes. Wilts kill the plants while nematoeds make them sickly. People try to sterilize soil using clear plastic tenetd a few inches above the soil to trap heat, but it doesn't always work well.

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Gary350
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Location: TN. 50 years of gardening experience.

This is what I read online. Blight can live in the soil for 5 to 6 years that is why you don't plant tomatoes in the same place they were the year before if you had blight because the plants will all catch blight again.

I had blight last year. I planted my tomatoes in a different location this year and the tomatoes have blight again.

I read you can sterlize the soil by cooking it in a large tub on the BBQ grill. This should work but I would think it would be a big job.

I have been spraying with a mix of copper sulfate and lime. One cup of lime, 1 tablespoon of copper sulfate, 4 gallons of water. Stir well and spray the plant top and bottom.

Last year my tomatoes were dead and gone the 3rd week of July. This year I am spraying and the plants look like hell but they are still producing tomatoes. I don't see how they can last much longer.

TZ -OH6
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Joined: Fri Jul 25, 2008 7:27 pm
Location: Mid Ohio

Blight (early blight) spores live in the soil for a long time, but the active organism does not. They won't become active/infective until contacting leaf/stem tissue after splashup or wind blown. They are very resistant to environmental conditions so sterilization methods that would kill active organisms (nematodes, wilts) would be fairly ineffective against spores. You would have to sterilize the whole yard because spores would be there too and blowing into the garden. Yes there can be a huge buildup in fields that are not cleaned of crop residue, I.e. dead plants are plowed under, but that is different than a garden where the plants are removed.

Late Blight, on the other hand, remains active in the living potato tubers, many of which sprout as volunteers the next year, reinfecting potatoes and tomatoes. This is a case where rotating the crops out for a year is necessary.

jimmykx250
Full Member
Posts: 38
Joined: Tue Jun 02, 2009 11:23 am
Location: Northern illinois

Every year when I plant tomatoes I put 2 layers of newspaper down and then grass clippings on top. I know tomatoes don't like to be wet so I'm carefull even when I water not to soak the entire plant even though the rain does a great job for me. So what I'm understanding is that moving the tomatoes to the other end of the garden wont do much good. I hate to resort to chemicals like copper but it looks like I wont have a choice. I'm happy with the harvest ive gotten this year but I will be better prepaired for next year. Thanks for all the advice,Jim.



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