A method for controlling a wind farm to damp low-frequency electrical oscillations, in particular subsynchronous resonances, in an electrical supply grid having a grid voltage with a nominal grid frequency is provided. The wind farm comprises at least one wind turbine connected to the electrical supply grid. The method includes sensing at least one low-frequency electrical oscillation of the electrical supply grid; determining an oscillation characteristic of each of the at least one sensed oscillation, the oscillation characteristic describing at least one property of the sensed oscillation; specifying an active-power damping signal and/or a reactive-power damping signal for damping the at least one low-frequency oscillation; feeding in an active power component in accordance with the active-power damping signal or a reactive power component in accordance with the reactive-power damping signal, the active-power damping signal and the reactive-power damping signal being specified in dependence on the determined oscillation characteristic.