It depends on the soil pH, where it's needed, crushed olivine is already used to increase crop yields (see e.g. https://modernfarmer.com/2023/09/enhanced-rock-w

It depends on the soil pH, where it's needed, crushed olivine is already used to increase crop yields (see e.g. https://modernfarmer.com/2023/09/enhanced-rock-weathering/ https://modernfarmer.com/2023/09/enhanced-rock-weathering/ ) where it's close enough / cheap enough. Bringing it everywhere where it could be useful, though, is unlikely to happen without subsidies to cover the transport costs, but the need for carbon capture might support that.