I think you'll appreciate it but will need more than grass. I would put the cardboard, then the grass, then at least 4" of mulch, but not treated or painted or bark chips (will float away when it rains) or any of the crud that is in bags @ a BBS. You should be able to find plain shredded hardwood in OH. A place like "Mr. Mulch" will deliver enough for a small bed or giant one. I wish there was something like that around here.
