Sterile soils are treated or pasteurized to sterilize any viable seeds and fungal spores.
Sterile soils are often contaminated during storage and handling.
Contaminated soil has no natural defense against unwanted organisms or pests, and requires additional treatment.
Living soils contain beneficial bacteria that promote plant health and vigor
Living soils contain nitrogen fixing bacteria that can improve soil.
Living soils can contain unwanted bacteria, as well as fungal spores and seeds.
It’s important to note that once exposed, either soil is susceptible to fungus nats, and infection by other pests.
So which is better?
We care less about the soil type that you start with, than we do a proper nutrient balance, moisture holding characteristics, aeration, PH, and a healthy rhizosphere. Unless we are using something like rockwool, clay balls, or perlite as a growing medium, we always inoculate our growing medium with beneficial bacteria.
If you are curious about beneficial bacteria, and the rhizosphere in general, then check out our post on mycorrhizal bacteria.