I know this is a long shot, but how feasible would cooking say 50-100 gallons of soil indoors be? I really like growing organically but I’m getting sick of paying Amazon prices $30-$40 1.5cuft roots original(no grow shop near me and I don’t drive because I have some medical problems that make passing out behind the wheel more likely than I’m comfortable with)
Can I just mix the peat(pro-mix hp), perlite and dry amendment blend(build-a-soil probably) in a big ass bin and then leave it for a month?
Very feasible. You may be a bit over $100 but you will easily be way ahead and can make some amazing soil... I ended up mixing 30 gals in a 50 gallon tote. And have enough to make way more I just only needed enough for my current grow. Screw buying 40$ bags of FFOF ever again. I'm sure they're great and convenient if your using salt based nutes but if your set on organic you can make a way better mix for much cheaper.
You can take this with a grain of salt as this is my first time using this mix. So far I have been very impressed, hope I found what works for me.
I read a lot of the "super soil" mixes on here all good stuff and suggest reading up on it. What most of the mixes break down to is a base mix- some close variation of 1/3 each of peat moss, aeration, and worm castings or compost. Then the amendments. This is when recipies get wild, there are many ways to cover your bases. After looking into the Gaia green and some dr earth fertz I decided to go that route since the are a pretty complete mix. I went with Dr earth home grown 4-6-3 and flower girl 3-9-4.
My base mix is 10 gal sphagnum peat moss, 10 gallons worm castings and big rootz, 10 gallons volcanic rock and clay pebbles.
My amendments are dr earth Homegrown at 1cup per 10gal. And I sprinkled about a half cup of flower girl in the mix. I also added a gallon of biochar.
Sprouted in happy frog(this bag of happy frog should last year's as I'm only using it for seedlings now) then transplanted to their final 4 gallon home with my mix. Plants just turned a month old, so far all I've done is water with tap water that's been left out for a day. I'm planning on having to top dress with flower girl at some point during flower.