It wasn't too long ago, a guy I knew was mixing up a batch of "super soil" and he decided it would be a good idea to add some organic, 4-4-4 tomato fertilizer. What he didn't realize was that it was also a soil acidifier (didn't read the small print!) because tomatoes like it. Long story short, he planted his plants in the mix and a few weeks later, everything was turning yellow, leaf necrosis, etc., etc. Did a slurry test and a runoff test....both were in the 4.0 range! "Well, there's yer problem!"
-by the way...that guy was me. heh heh