Leromeanswered grow question 3 months ago Hey, i would suggest to remove as many old roots as you can before re-using soil, as they can become a breeding chamber for pests like fungal root infections.
You could also cycle your pots, the roots will decompose over time (it takes patience, you should wait at least 1 year, better 2 or 3) and meanwhile you can plant any other plant than cannabis or hops into that soil. The roots of another plant species will not be problematic, just from the same species or family its dangerous to plant into rotting roots.
If you consider this you can recycle your soil. Make sure to reamend what you estimate has been taken from the soil in the previous grow.
Good luck!