Washington Boro, Pa. - This year has been a challenge for Steve Funk. With 12,000 staked tomatoes growing at his Washington Boro farm, he is battling the late blight; the same disease which caused the 1845 Irish Potato Famine.

Late blight also kills tomatoes.

"These are the worst weather conditions I have seen in my lifetime of raising tomatoes," Funk said. "I've never seen it stay so rainy and cloudy all season long."

The disease causes the appearance of dark blotches on leaf tips and plant stems.

"You might think your plant is healthy one day and the next day you'll see some spotting on it and the leaves kind of curling around, turning brown," said Tracey Olson, a plant pathologist for the Pa. Department of Agriculture (web | news) .

Not only does the plant die once it's been infected, but the disease spreads to other plants. The mold spores can travel for miles, infecting other gardens and commercial growers

"I keep my tomatoes covered with plastic," Funk said. "The plastic keeps the rain off the tomatoes, keeps the dew off the tomatoes in the morning and it protects the tomatoes from getting blight conditions."

Our cool and damp weather has been nearly perfect for the disease to grow and spread. There hasn't been a day that reached 90 degrees since May, and while that may be delightful for us, it can be deadly for tomatoes.

"Tomatoes like it hot and dry," Funk said. "When its not hot and dry and you get a lot of rain, this will cause blight conditions."
If the blight is affecting your tomato plants, it's too late to save them.

"Pull those plants from the ground, put them into a nice garbage bag and tie it up and then leave it in the sun for a couple of days," Olson said. "That will certainly would kill the plant as well as the organism."

If you think your plants are infected with the blight, you can take a sample to your local Penn State Ag Extension Office.

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