What state do you live in, jerryday? Can't say anything because I live in Texas Hill Country where you would have to bring in topsoil, there's only (I think) 4 inches of topsoil here before hitting either rocks or cement-hard clay. We buy a lot of dirt.
But, I would recommend starting a compost pile, starting with this fall's leaves if you haven't already, ash from fireplace this winter.
Farmerman recommended annual rye. We did that once, had beautiful green grass that turned black in summer. So, do you just turn this stuff over next spring? Haven't tried it on a garden.