I highly suspect that you may have compaction and nitrate issues in your land. I would recommend working a layer of bark into the soil before adding anything to the bed. Tookalisten's suggestion of 1/3 compost, 1/3 vermiculite, and 1/3 peat moss is a great idea over that. I would avoid using extra fertilizer for the first two years that you plant. your plants may be a little smaller, but you will be giving the soil a nice long chance to adjust to the changes. It will also give the soil a chance to get rid of extra salts that may affect planting.
I have found that in reclaimed land, mycoremediation works very well. In fall, spread leaves over your beds and just let it sit through the winter. A nice thick layer so that fungus can find a good home underneath it. There are some products that can spur the process, but it's not strictly necessary. Eventually you will see toadstools popping up in the garden and even in your lawn if you have one. That's good, don't try to get rid of them.
That layer of bark underneath your filling will allow roots to find breathing space. It will break down over time and help to solve compaction problems caused by repeated corn planting and by the construction process. Take note of any "puddly" areas and dig an extra layer of compost into them. The soil will thank you.
I hope this helps