Tomato blight - need help (tomatoes, Arizona, vegetables, spring)

[GregW]

My tomato plants are being attacked by something that kills the leaves by covering them with brown/black spots and then turning them yellow. It also kills off the stems. Some of the leaves turn to a grey powder and fall off.

I have removed the yellow and the dead grey leaves. This has stripped most to the old leaves off the bottoms of the plants. The tomatoes and the new leaves are still OK.

I have dusted these plants with basic copper sulfate but it does not seem to have any effect. Please help because I want to salvage this year’s crop and avoid this next year.

[BlueWillowPlate]

A lot of people, myself included, have been fighting off tomato problems this year.
I really don't recognize your grey leaf situation. A fungus?
I've been battling a situation involving first the plant turning yellow, then dying and brown. I think it was teeny tiny mites.
I used Pyola. I've sprayed about 4 times now. I finally gave up on two different tomato plants, the others seem okay.

[pitt_transplant]

"Other fungicides such as chlorothalonil (Bravo, Daconil) and azoxystrobin (Quadris) are effective in preventing disease."


tomato Alternaria early blight

[swbtoo]

I got a natural fungicide from springtimeinc.com for blight and that worked. We only lost one plantto blight, though there were 20 others in proximity. But that was because we were too late in identifying the problem.

Among the suggestions I got from our county extension office is "don't water in the evening. Water in the morning so that the plant has a chance to dry during the day."

[Blue Grass Fever]

Originally Posted by southward bound

I got a natural fungicide from springtimeinc.com for blight and that worked. We only lost one plantto blight, though there were 20 others in proximity. But that was because we were too late in identifying the problem.

Among the suggestions I got from our county extension office is "don't water in the evening. Water in the morning so that the plant has a chance to dry during the day."

To add to your county extension office's advice is to not get the leaves wet which can cause problems for your tomatoes.

The thing to do is soak your plants at root (flooding concept) level with a soaker or just lie the hose down and let it run and move it around periodically to ensure all plants get a good soaking.

[Nomadicus]

If you know there is blight in your garden I would suggest researching varieties that are blight resistant for next season. Sometimes it is a trade off if you want heirloom open pollinated tomatoes instead of a modern hybrid. Disease resistance has been bred into some mighty fine hybrid tomatoes. Check with your county ag specialist for recommended varieties for you area. Just my 2¢.

[GregW]

Thank all of you for your advice. I just started using a chlorothalonil based spray. I was using basic copper sulfate but it did not seem to have any effect. I will set up a soaker hose next season. Good idea.

[Maine Writer]

You can help slow down the spread of blights by mulching with straw after the soil has finished warming. Disease splashes up from the soil onto the plants. Straw will stop the splashing.

[paperhouse]

I took my dad's advice this year. I made the bed, planted the seeds and seedlings, then I laid down a soaker hose, covered the whole garden in leaf mulch. No disease, nothing. Still getting fresh tomatoes.

[swbtoo]

I suspect that we introduced the blight this year through the bags of garden soil we added to the raised beds. Do you think that's possible?

Fortunately, we caught it early and only lost one tomato plant. We didn't have any problems last year, but we also didn't add soil.