Montmorillonite (Calcium Bentonite) is a premium-grade clay mineral sourced from Australia's world-class bentonite reserves — widely regarded as the "Cadillac of Clays" in soil building. Its primary role is increasing the cation exchange capacity (CEC) of your soil, helping it hold onto nutrients rather than letting them leach away with watering.
Calcium bentonite is commonly used to convert sandy, free-draining substrates into something with real nutrient-holding power. It also provides a source of exchangeable calcium, supporting cell structure and soil flocculation. Because it's a true clay mineral, it will hold significant water — which is a benefit in moderation but means it should be added sparingly and incrementally.
