Soil Reuse advice needed

my soil gets rotated. I have three rubbermaid tubs Stacked up. When my plants are harvested, I add some enzymes solution to the pot and let it sit two weeks. Then I cut out the stem and the tight ball of roots. Chop up the remainder of the roots and soil, fill a rubbermaid tub. Mix in 1/2 cup of dry organic fertilizer (Happy Frog, Coast of Maine etc), half gallon of worm castings, I then pour in a half gallon of natural Humboldt Nutrients mixed at 5 week schedule. Cover and it sits until I need it. Sometimes I may take one out on the patio in the sun next to my chair, for a place to hold my beer. it is a win-win