I woke up this morning and took a good look at the 7 potted tomato plants I have growing on my deck. Looked great. But I came home this evening and found white spots around the edges of leaves on four of 7 plants (all different varieties). What is this stuff?
I'm worried that it showed up so quickly and would love to get a jump on stopping it if it's something I need to be concerned about.
The closets thing I've found in my online searches has been white powdery mildew, but these look different than most of what I saw so I'm just not sure. I scraped off a bit of the white stuff and took a look at it under a microscope but that didn't help me identify it. Thanks for any help