Q: Every year I fight this in my tomatoes. I have been diligent in spraying with fungicide. Now it appears to be getting beyond control. I have used Serenade mostly. Is there anything else I can use that will control or prevent this dastardly disease?
A: The disease is a common one on tomatoes: early blight. It starts when soil splashes up onto lower leaves and progresses upward from there.
According to UGA plant pathologist Elizabeth Little, Serenade, a fungicide that contains a unique strain of Bacillus subtilis, does not have much curative action. It would be important to apply before there is much evidence of disease. Apply every week from the day your tomatoes are planted. It works by preventing spore germination, so it needs to be there before the spores find the plant.