Promix for containers is what Im looking for but on the west coast it's near impossible to find it. So heres the question: Can I swap out the pro mix for sun gro all purpose planting mix. Promix for containers: Canadian Sphagnum Peat Moss, water absorbent polymer, perlite and limestone. Sun gro: Canadian sphagnum peat moss, horticultural grade perlite, dolomite lime and a wetting agent. I am planning on mixing 1 bag of miracle grow organic + 1 bag of pro mix + 1 cup blood meal + 1 cup bone meal + 1/2 cup dolimite lime + 10-20% added chunky perlite. Edit: Is it possible to replce the promix with any thing that pretty much has the same exact ingredients?