Method for controlling a wind turbine (100, 302) having an aerodynamic rotor having rotor blades which can be adjusted in terms of their blade angle, comprising the steps of: - operating the wind turbine (100, 302) in a part-load range, - at a rotor speed below a nominal speed (n N) and - having a power output below a nominal power, - using - a speed/power characteristic line which indicates a relationship between a rotor speed which is adjusted depending on the prevailing wind and a power output which is intended to be adjusted, or - a speed/torque characteristic line which indicates a relationship between a rotor speed which is adjusted depending on the prevailing wind and a torque which is intended to be adjusted, - adjusting - a power output according to the speed/power characteristic line, or - a torque according to the speed/torque characteristic line, wherein - the speed/power characteristic line or the speed torque characteristic line has in the range of a problem speed (n p) which is intended to be avoided a hysteresis range, and wherein the wind turbine (100, 302) is operated in such a manner that - with increasing wind up to a lower limit speed (n u), a power output according to the speed/power characteristic line is adjusted or a torque according to the speed/torque characteristic line is adjusted, - from the lower limit speed (n u) with further increasing wind, the rotor speed is kept substantially constant and the power output or the torque is increased until the power output has reached an upper limit power (P o), or an upper limit torque is reached, and - when the upper limit power (P o) or the upper limit torque is reached, after waiting for a predetermined switching delay, the rotor speed is increased to an upper limit speed (n o), in particular is increased as rapidly as possible, in order to pass the problem speed (n p), and - with further decreasing wind, when the rotor speed is initially above the upper limit speed (n o) up to the upper limit speed (n o), a power output is adjusted according to the speed/power characteristic line, or a torque is adjusted according to the speed/torque characteristic line, and - from the upper limit speed (n o) with further decreasing wind, the rotor speed is kept substantially constant and the power output is decreased until the power output has reached a lower limit power (P u) or the torque is decreased until a lower limit torque is reached, and - when the lower limit power (P u) is reached or the lower limit torque is reached after waiting for the predetermined or another predetermined switching delay, the rotor speed is decreased to the lower limit speed (n u), in particular decreased as rapidly as possible, in order to pass the problem speed (n p). - operating the wind turbine (100, 302) in a part-load range, - at a rotor speed below a nominal speed (n N) and - having a power output below a nominal power, - using - a speed/power characteristic line which indicates a relationship between a rotor speed which is adjusted depending on the prevailing wind and a power output which is intended to be adjusted, or - a speed/torque characteristic line which indicates a relationship between a rotor speed which is adjusted depending on the prevailing wind and a torque which is intended to be adjusted, - adjusting - a power output according to the speed/power characteristic line, or - a torque according to the speed/torque characteristic line, wherein - the speed/power characteristic line or the speed torque characteristic line has in the range of a problem speed (n p) which is intended to be avoided a hysteresis range, and wherein - with increasing wind up to a lower limit speed (n u), a power output according to the speed/power characteristic line is adjusted or a torque according to the speed/torque characteristic line is adjusted, - from the lower limit speed (n u) with further increasing wind, the rotor speed is kept substantially constant and the power output or the torque is increased until the power output has reached an upper limit power (P o), or an upper limit torque is reached, and - when the upper limit power (P o) or the upper limit torque is reached, after waiting for a predetermined switching delay, the rotor speed is increased to an upper limit speed (n o), in particular is increased as rapidly as possible, in order to pass the problem speed (n p), and - with further decreasing wind, when the rotor speed is initially above the upper limit speed (n o) up to the upper limit speed (n o), a power output is adjusted according to the speed/power characteristic line, or a torque is adjusted according to the speed/torque characteristic line, and - from the upper limit speed (n o) with further decreasing wind, the rotor speed is kept substantially constant and the power output is decreased until the power output has reached a lower limit power (P u) or the torque is decreased until a lower limit torque is reached, and - when the lower limit power (P u) is reached or the lower limit torque is reached after waiting for the predetermined or another predetermined switching delay, the rotor speed is decreased to the lower limit speed (n u), in particular decreased as rapidly as possible, in order to pass the problem speed (n p).