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Late Potato/Tomato Blight
In the past week, there has been a lot of media coverage of the Late Potato Blight, which also affects tomatoes. We do not feel that is a threat to home gardeners in our area in most circumstances. The disease has been tracked to some Bonny Plants brand plants, which are shipped to big box stores. Locally grown tomato plants have shown no signs of the disease; the only concern to local growers would be if a neighbor purchased a shipped-in plant from out of state and the spores of the disease were windborne. No local cases have been positively identified. If, after reviewing these photos and descriptions, you believe you may have a case of the blight, please take a sample in a sealed ziplock bag to your local County Extension Office for identification and monitoring. Their contact information can be found on our "Links" page. The following are websites with detailed information and photos of the problem: Excellent Disease Photos from Cornell Ohio State Agriculture Hartford Courant
According to Cornell: "Here are the steps you should take: Examine your tomato and potato plants thoroughly at least once a week for signs of late blight. Spray fungicides (Knollwood: such as Daconil or Fungonil) preventively and regularly and/or be prepared to destroy your plants when late blight starts to become severe. Seal them in a plastic bag. Do not put them in the compost pile. Leave the bag ‘cooking’ in sunlight for several hours to kill plant and pathogen, then put in the trash. Fruit can rot quickly once infected, but any part not affected is safe to eat as this pathogen does not produce a toxin. If you want to try to control late blight with fungicides, you need to begin spraying fungicide now – even before you see symptoms – and you need to continue spraying regularly. Use a product that contains chlorothalonil. Copper is not very effective on late blight."