A gardening tool, such as a mower, includes a main body and a handle rotatably connected to the main body. The main body includes a motor. The handle includes a plurality of telescopic members slidably connected to each other. The mower further includes a operation assembly for being operated by a user to activate the motor and a control system for sending a control signal to enable or disable the operation of motor by the operation assembly when the handle is out of a secure state.