Not too late Rick, I haven't made the order for all the materials at Lowe's yet. I'm actually waiting for a reply back from 'Black Kow' the company that makes this topsoil as to how many cubic feet a 40lb bag may contain. I'll also be adding some of their compost to the mix. Their topsoil is lots less expensive than potting soil or garden soil. The only potting soil I use for all my plants is EcoScraps. It's a bit more expensive but a lot better than MG.
Thanks for the suggestions.