Aerodynamic root adapters for rotor blades include an interior support section having a first end that connects to a root end of the rotor blade and a second end that connects to a rotor hub of the wind turbine, and, an aerodynamic exterior section supported by the interior support section. The aerodynamic exterior section thereby extends an aerodynamic profile of the rotor blade beyond the root end of the rotor blade to at least partially between the root end of the rotor blade and the rotor hub when the aerodynamic root adapter is connected thereto.