Tomato Plants Browning/Dying
Any help identifying the problem with my plants would be appreciated.
I have about 25 plants in a raised bed, next to a few peppers and eggplants. The soil is loose, filled with mushroom compose, vermiculite, top soil, and hardwood fines. It's been in use about 5 years. The tomatoes themselves are grown from seeds, mostly heirloom, with a few saved from last year (mixed variety).
Most of the plants are exhibiting some degree of the problem. The leaves are getting brown spots on them. They are not little or round, rather oblong splotches that spread across the leaves. They leaves brown, then the branch yellows, and eventually falls off. The splotches cover both sides of the leaf.
Some leaves exhibit holes, but not all. I found one leaf with tiny little green (eggs?) on one side, but none on the other. Some plants are much more effected than others. The worst, by far, is a plant on the farthest side, near a cedar fence and closest to an empty lot opposite my yard. This plant is clearly dying. Some others have only small amounts of brown spots, but it appears to be spreading.
I thought fungus at first, and treated with green cure, bio-neem, and one other organic fungicide. This had no effect.
It seems like insect damage from the way it's so heavy on certain plants, but I can so no evidence of spider mites or the like on the plants.
Any idea how to figure it out?