Monday, June 8, 2009

Help For Tomatoes With Brown Spots

Question: My tomato plants lower limbs are turning brown, otherwise the
plants look healthy with blooms and small tomatoes. I am doing nothing different
as I have always done as far a fertilizer and water. Can you help me with this
and what I can do?

It sounds like Early Blight which is a fungal disease that occurs early in the season. There are several diseases that affect tomatoes and they occur for different reasons which can vary from year to year. So, while you may not have had problems last year, that does not guarantee that the next year will be the same even if you are doing the same thing. For one thing, we've had a lot of rain and cloudy days which will always promote fungal disease. It is important to mulch your tomatoes well for several reasons, one of them being that it will help prevent soil-borne disease from splashing up onto the plants when it rains. Also, do not work around the plants when they are wet since you yourself can be a disease vector by touching and spreading it. It's a good idea, if you have the room for it, to plant the tomatoes in a different spot each year since diseases will build up in the soil from year to year.

Once you have the diseases, there is not a lot you can do but here's a few things that can help: Remove the affected branches right away when you see them, mulch the plants, do not water in the evening and try not to overhead water the plants. Instead water only over the root area. Increase air circulation in the area if possible by removing non-essential plants and weeds that might be crowding the tomatoes. You can try Serenade Disease Control an organic spray for diseases. It is better as a preventive than a curative, but it will probably slow the progression of the disease and help prevent the start Septoria leaf spot and late blight, two other tomato diseases that are prevalent. Lastly, if you smoke make sure not to do so near the tomatoes and wash your hands before handling the plants. Tobacco carries a disease that can easily jump to tomatoes.

-Tina Mast, Communications Director