Piezoelectric actuators for synthetic jets and other devices are disclosed having orthotropic piezoelectric bimorphs with increased out-of-plane displacements for greater responsiveness to applied electric fields. In some embodiments, the piezoelectric actuators may include interdigitated electrodes applied to a surface of a piezoelectric plate to produce greater in-plane strains in the plate and greater out-of-plane displacements of a flexible diaphragm of the synthetic jet. In other embodiments, the actuator includes an orthotropic piezoceramic plate having a greater d coupling coefficient in one in-plane direction and in the other in-plane direction to cause desired diaphragm out-of-plane displacements when an electric field is applied by electrodes.