This paper studies the steady, free convection boundary layer flow about a vertical, isothermal plate embedded in a non-Darcy bidisperse porous medium (BDPM). An appropriate mathematical model is proposed. The boundary layer analysis leads to a system of partial differential equations containing inertial, interphase momentum, thermal diffusivity ratio, thermal conductivity ratio, permeability ratio, modified thermal capacity, and convection parameters. These equations that govern the flow and heat transfer in the f-phase and the p-phase are solved numerically using an algorithm based on the bvp4c routine from matlab. The dependences of the dimensionless velocities and temperatures profiles, as well as of the Nusselt numbers on the governing parameters are investigated. The features of the flow and heat transfer characteristics for different values of the governing parameters are analyzed and discussed in details.