Abstract An analytical study of natural convection from an isothermal or uniform wall‐heat‐flux vertical, heated plate embedded in a porous medium is presented. The Brinkman's equation of the non‐Darcy model with boundary effect is employed. Based on the scaling analysis of order‐of‐magnitude, two natural convection parameters are introduced; ζ = (RaxDax )½ is for the isothermal case and ζ*=Ra* x ? Dax ½ for the uniform wall‐heat‐flux case, with ξ = ζ/ (1 + ζ) or ξ = ζ*/(l + ζ*). These parameters not only represent the ratio of the viscous sublayer thickness to the thermal layer thickness, but also denote a measure of the boundary effect on the buoyancy‐induced flow and heat transfer characteristics. Furthermore, we use the dimensionless variables transformation in terms of ξ to transform the governing boundary layer equations into a system of nonsimilar equations. An accurate, implicit finite difference method is thus employed to solve these nonsimilar equations. The numerical solutions obtained are foun...