Great tip on the egg shells. BER is my biggest trouble with tomatos (other than hail). I will give that a shot this spring.

A couple of things I use to build the soil (and hold it in place). I will plant a buckwheat cover crop in unused portions, let it grow for around 6 weeks and cut it right before it goes to seed, then turn it under after sitting down for about a week. Sometimes I do multiple crops during the summer.

The other crop I have tried is Annual Rye grass sown in the fall and turned in the late winter.

Another I want to try in clover, may do a section of one spot this spring and follow it with some fall crops.