How to Build a Batch of Soil?

[Gitane]

I've got about 25 cubic feet of used Edna's Best Potting from the last few grows. I assume all nutrients are depleted. I used organic fertilizers during the grows (Earth Juice).
Per Edna: "contains Aged Fir Bark, Sphagnum Peat Moss, Aged Redwood, Volcanic Pumice, Earthworm Castings, Washed Sand, Kelp Meal, Bat Guano, Feather Meal, Gypsum and Mycorrhizae.Oyster Shell Lime and Dolomite Lime are added as pH adjusters. A natural wetting agent, Yucca shidegera saponin, has been added to help remoisten the product."
What additives and in what amounts should I use per gallon of this used soil. (worm castings, dolomite lime, nitrogen source, etc)
Or should I just continue to buy new bags each year?

 

[vastok]

,,just continue to buy new bags each year? ...is what most of us do, its a hassle for I'm like you, but its worth contracting the soil making side out, as I buy in fresh each year from the hippies down at the river, they are a very popular guys in our village, and supply local tomato and veg farmers too, it will take some finding but once found in your area...hang on to them, the last years soil is used in my garden to supply nutes to my veg and fruits

 

[NateToke]

You might get better results if you post the in the organic section. Or Google "organic marijuana soil". Lots of info out there if you go look for it.