Rrog,I mixed up some soil from your recipe but made a few substitutions to use up what I already had. I used blood meal instead of fish meal,then potash,sulfur and epsom salt instead of sul-po-mag then for my rock powders I used 2 cups GRD,1/2 cup bentonite,1/2 cup oyster shell,1/2 cup azomite and 1/2 cup excelerite. I also decided to try growstone instead of perlite and a $32 2-CF bag was enough to make 5 CF of mix. Any thoughts on my subs and have you tried growstone? Is 30 days the minimum wait to be able to use this? I was also going to add the nematodes and BTI when I plant in it. Where do you get your nematodes from?