I just got the following alert from a friend

“Late blight has been confirmed on tomato plants in Poughkeepsie. If you live within a 30 mile radius of Poughkeepsie, you may wish to consider using fungicides to protect your tomatoes and potatoes. This site has some very good photos of late blight on tomato plants. Fungicide recommendations can be found in this Cornell fact sheet.”

For those of you who were gardening in 2009, you’ll remember what a disaster this disease can be. For those of you who weren’t, this is the disease that caused the Irish Potato Famine. It affects both potatoes and tomatoes and kills them very quickly. The disease is not curable once the plant has it, you can only prevent your plants from getting the disease.

Prevention can be done using what are called cultural methods including pruning, watering at ground level, watering in the middle of the day, and spacing the plants widely. All of these things will helps plant leaves dry off quickly which will tend to discourage the disease. There are fungicides that can also be used, some of which are listed in the article linked above. If you are trying to grow your vegetables organically, you’ll need to use either one of the copper products or one containing Bacillus subtilis.