How often do you apply it to your tomatoes and at what point do you start?
There's lots of info on the internet, but I use a 2% solution in a Windex bottle and spray the plants and the ground around them after they get about a foot tall. It doesn't take much, but I respray after rains. Grapes, apples, berries and peppers get a direct application, but I start spraying grapes before the leaves or flowers come out as black rot can be in dead areas of the vine.