3D heteroepitaxial growth of BiFeO3-CoFe2O4 nanostructures leads to unique morphological patterns depending on the substrate orientations. The morphologies of the BiFeO3-CoFe2O4 nanostructures, estimated using the Winter-bottom construction (see figure), are dependent on the different nucleation modes that result from the differences in surface energy anisotropy. The dimensions of the BiFeO3-CoFe2O41 nanostructures increase as the growth temperature increases and decrease as the growth rate increases.