Reconditioning soil after grow?

If you want to reuse the medium over a few times it needs to go though a phase where it composts a bit and is ready for new life. It then needs to be fortified with minerals and organic matter that was lost in the last grow. One quick way of doing this is to toss it into a pressure cooker and zap it so its sterile and then fortify it. More life will be needed in the soil like worm castings or you will run into problems with this method as the pressure cooker is killing most of the life in the soil, good and bad. Its not like the earth outside is getting new soil, when farmers grow they cycle crops and refortify the soil with manure/green manure. When we grow with much smaller amounts of soil we need to really add a lot more into it as we don't have the luxury of it being outside. To make it stupid simple toss your old soil in the garden and grow some tasty veggies with it, get new stuff when you want. I myself plan on reusing my medium a few times and will compost it in batches on my deck in a black garbage bag before incorporating it into the garden. Best Of Luck!