A method for filling a tank system of an agricultural sprayer with a liquid spraying material, comprising: - providing an agricultural sprayer having a spraying system comprising - a tank system provided with a first tank and an second tank both configured to receive a spraying material being a liquid mixture containing water and chemical; - a pump device; - a dispensing device having a plurality of nozzles configured to dispense the liquid mixture; - a pipe system connected to the first tank, the second tank, the pump device, and the dispensing device; and - a control device configured to control at least a filling process of the tank system; and - filling the first tank with a first target volume of the liquid mixture and the second tank with a second target volume of the liquid mixture in the filling process controlled by the control device, the liquid mixture being provided with a predetermined concentration of the chemical in both the first tank and the second tank, comprising - providing filling data indicative of the first target volume and the second target volume in the control device; - filling the first tank with a basic volume of the liquid mixture, the basic volume of the liquid mixture containing a total amount of the chemical to be provided in the first tank and the second tank; - determining a transfer volume of the liquid mixture by the control device, the transfer volume being smaller than the basic volume and containing a part amount from the total amount of the chemical to be contained in the second target volume of the liquid mixture in the second tank; - transferring the transfer volume of the liquid mixture from the first tank to the second tank through the pipe system; and - filling the tank system with additional water for providing the first tank with the first target volume of the liquid mixture and the second tank with the second target volume of the liquid mixture, the liquid mixture containing the chemical with the predetermined concentration in both the first tank and the second tank. - providing an agricultural sprayer having a spraying system comprising - a tank system provided with a first tank and an second tank both configured to receive a spraying material being a liquid mixture containing water and chemical; - a pump device; - a dispensing device having a plurality of nozzles configured to dispense the liquid mixture; - a pipe system connected to the first tank, the second tank, the pump device, and the dispensing device; and - a control device configured to control at least a filling process of the tank system; and - a tank system provided with a first tank and an second tank both configured to receive a spraying material being a liquid mixture containing water and chemical; - a pump device; - a dispensing device having a plurality of nozzles configured to dispense the liquid mixture; - a pipe system connected to the first tank, the second tank, the pump device, and the dispensing device; and - a control device configured to control at least a filling process of the tank system; and - filling the first tank with a first target volume of the liquid mixture and the second tank with a second target volume of the liquid mixture in the filling process controlled by the control device, the liquid mixture being provided with a predetermined concentration of the chemical in both the first tank and the second tank, comprising - providing filling data indicative of the first target volume and the second target volume in the control device; - filling the first tank with a basic volume of the liquid mixture, the basic volume of the liquid mixture containing a total amount of the chemical to be provided in the first tank and the second tank; - determining a transfer volume of the liquid mixture by the control device, the transfer volume being smaller than the basic volume and containing a part amount from the total amount of the chemical to be contained in the second target volume of the liquid mixture in the second tank; - transferring the transfer volume of the liquid mixture from the first tank to the second tank through the pipe system; and - filling the tank system with additional water for providing the first tank with the first target volume of the liquid mixture and the second tank with the second target volume of the liquid mixture, the liquid mixture containing the chemical with the predetermined concentration in both the first tank and the second tank. - providing filling data indicative of the first target volume and the second target volume in the control device; - filling the first tank with a basic volume of the liquid mixture, the basic volume of the liquid mixture containing a total amount of the chemical to be provided in the first tank and the second tank; - determining a transfer volume of the liquid mixture by the control device, the transfer volume being smaller than the basic volume and containing a part amount from the total amount of the chemical to be contained in the second target volume of the liquid mixture in the second tank; - transferring the transfer volume of the liquid mixture from the first tank to the second tank through the pipe system; and - filling the tank system with additional water for providing the first tank with the first target volume of the liquid mixture and the second tank with the second target volume of the liquid mixture, the liquid mixture containing the chemical with the predetermined concentration in both the first tank and the second tank.