posted 1 year ago
I quench my biochar with water at the end of a burn, so it's wet from the beginning. Drenching it with high-microbial liquids is my preferred inoculation method and even though the material does not absorb all the effluent, it sits in contact for long enough that I'm confident the colonisation takes place. Biochar spread on the ground will actively take in soil bacteria and I think this is a valid means of charging it as well, especially if it's in an area that you're not currently growing crops (mostly because this phase can temporarily deplete the soil biota, but I think this risk is way overstated).
Another thing to keep in mind is that any inoculation we do intentionally will just be a "pioneer" effort. Once the stuff is in the soil, a whole new set of species may end up taking residence in there and they might consume the initial inhabitants in doing so. These are complex dynamic systems we're dealing with, after all...time, temperature, moisture levels, environmental conditions like different root exudates from varying types of plants, all will have effects.
I don't think a little dirt will harm anything since it's destined for the soil anyway. The only negative effect would be if you were trying to crush the biochar with a implement that could be damaged by rocks. How big are the pieces?