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We have a food bank garden in Monroeville, PA and have had successful years with tomatoes and other vegetables. But this year there are dark area...
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We have a food bank ... #145716
Asked August 06, 2013, 11:08 PM EDT
We have a food bank garden in Monroeville, PA and have had successful years with tomatoes and other vegetables. But this year there are dark areas appearing on the unripe tomatoes that don't look like early blight or sun scald. There are dark areas on the skin that can be one small spot or sometimes covers 1/3 of the green tomatoes. We have no idea why this is happening or how to treat it. It isn't a soft area and appears usually somewhere near where the stem holds the tomato. But can be on other areas. Since the transplants were donated, we don't know their varieties. The only differences this year is that we got the transplants from a different source and also the compost was bought from a different nursery. Another possible contributing factor is much much more rain this spring and summer. We think it might be graywall or late blight but don't know what to do about it. We were hoping for help from your community. I've included pictures this timeAllegheny County Pennsylvania
Expert Response
That certainly looks like late blight. The conditions have been right for it to develop. To be sure, I would advise you to take a plant sample to your nearest extension office for analysis. We (PSU Extension) really try to track the progression of late blight, so if you are able to take the sample in, that would be wonderful. Infection initially
appears as water soaked lesions on the leaves and stems. Under cool and moist conditions, the fruits
may become infected initially with firm, dark brown lesions
that rapidly become enlarged, wrinkled, and somewhat sunken. The rotted areas are usually located on the
top of the fruit and may remain firm or become mushy.
Both green and ripe tomatoes can be
infected. Green fruit that is picked
early and ripened indoors may develop symptoms before it is ready to eat. If the plants are severely infected, be
prepared to destroy them. Remove the entire plant and discard in a garbage bag. Unfortunately, once the disease is that progressed, there isn't much you can do to save the plant. It is best to destroy the affected plants before it has a chance to spread to others.
Almost all of the plants have the blight. We have ordered an organic fungicide as the zucchini plants are very moldy. Could this fungicide help with the blight? It would be terrible after all our work to have nothing but rotten vegetables. The food banks have come to depend on us in the summers.You can try it, but I haven't seen it work very well beyond a certain point. That's why late blight is so devastating. You kind of have to be treating it before you even know you have it. If you have any plants that aren't affected, maybe treating will help. Here's a site to PSU Extension so you can read more about it: http://extension.psu.edu/plants/vegetable-fruit/fact-sheets/tomato-potato-late-blight-in-the-home-garden/view.
Asked August 06, 2013, 11:08 PM EDT
We have a food bank garden in Monroeville, PA and have had successful years with tomatoes and other vegetables. But this year there are dark areas appearing on the unripe tomatoes that don't look like early blight or sun scald. There are dark areas on the skin that can be one small spot or sometimes covers 1/3 of the green tomatoes. We have no idea why this is happening or how to treat it. It isn't a soft area and appears usually somewhere near where the stem holds the tomato. But can be on other areas. Since the transplants were donated, we don't know their varieties. The only differences this year is that we got the transplants from a different source and also the compost was bought from a different nursery. Another possible contributing factor is much much more rain this spring and summer. We think it might be graywall or late blight but don't know what to do about it. We were hoping for help from your community. I've included pictures this time
Allegheny County Pennsylvania
Expert Response
That certainly looks like late blight. The conditions have been right for it to develop. To be sure, I would advise you to take a plant sample to your nearest extension office for analysis. We (PSU Extension) really try to track the progression of late blight, so if you are able to take the sample in, that would be wonderful. Infection initially
appears as water soaked lesions on the leaves and stems. Under cool and moist conditions, the fruits
may become infected initially with firm, dark brown lesions
that rapidly become enlarged, wrinkled, and somewhat sunken. The rotted areas are usually located on the
top of the fruit and may remain firm or become mushy.
Both green and ripe tomatoes can be
infected. Green fruit that is picked
early and ripened indoors may develop symptoms before it is ready to eat. If the plants are severely infected, be
prepared to destroy them. Remove the entire plant and discard in a garbage bag. Unfortunately, once the disease is that progressed, there isn't much you can do to save the plant. It is best to destroy the affected plants before it has a chance to spread to others.
prepared to destroy them. Remove the entire plant and discard in a garbage bag. Unfortunately, once the disease is that progressed, there isn't much you can do to save the plant. It is best to destroy the affected plants before it has a chance to spread to others.
Almost all of the plants have the blight. We have ordered an organic fungicide as the zucchini plants are very moldy. Could this fungicide help with the blight? It would be terrible after all our work to have nothing but rotten vegetables. The food banks have come to depend on us in the summers.
You can try it, but I haven't seen it work very well beyond a certain point. That's why late blight is so devastating. You kind of have to be treating it before you even know you have it. If you have any plants that aren't affected, maybe treating will help. Here's a site to PSU Extension so you can read more about it: http://extension.psu.edu/plants/vegetable-fruit/fact-sheets/tomato-potato-late-blight-in-the-home-garden/view.