Throwing out thirty litres of soil after each CBD harvest is expensive and unnecessary if the previous plants were healthy. Breaking up the root ball, adding compost, worm castings and a dry amendment mix, then resting it for a month restores most of the fertility. The soil recycling recipe on https://calmcbdseeds.com lists amendment ratios per ten litres and notes that reused soil suits CBD lines better than heavy feeders. Any medium that held a plant with root rot or pests should still go straight in the bin.
