The present disclosure is directed to methods for manufacturing wind turbine rotor blades and components thereof. In one embodiment, the method includes forming an outer surface of a rotor blade panel from one or more fiber-reinforced outer skins. The method also includes printing and depositing at least one reinforcement structure onto an inner surface of the one or more fiber-reinforced outer skins to form the rotor blade panel, wherein the reinforcement structure bonds to the one or more fiber-reinforced outer skins as the reinforcement structure is being deposited.