It's been a really cool, wet summer here, and I feel like I'm being overrun with different fungal diseases. It started with black rot in my kale, which has spread, despite tearing out the initial planting and spraying all my other brassicas with copper soap.
Of course my tomatoes are affected. I mowed down all my parsley because of a leaf spot, my melons just bit the dust, and walking thru this morning, I noticed rectangular lesions on the leaves of my sweet corn (which is almost ready).

I'm a little freaked out, especially about the black rot. I've read all about it, and I'm hoping that crop rotation, and keeping culls out of the compost will prevent a re-occurrence next year. I'm spraying copper weekly on my broccoli, cabbages and cauliflower, and I'm still seeing evidence of the disease, although it's slowed down.

Questions: Has anyone used Actinovate for preventing fungus? I know it's not supposed to prevent black rot, but I'm seeing sooo many different diseases.
Any other recommendations for helping with disease (I already use lots of compost, follow the organic amendment recommendations from Logan labs and rotate crops - in blocks - I'm thinking of separating my beds of brassicas and tomatoes next year so that disease can't go thru the entire block so quickly)
Also, would you just pull all the brassicas and take the loss, or can I allow stuff to mature? From what I read, the disease is systemic, and if it's on the leaves, it's infected the entire plant(!) but my cabbages are heading nicely, despite it all.

Thanks!