An apparatus and method is described herein for providing speculation control instructions. More specifically, the present invention relates to a method of introducing a florigen into a cell of a shoot apical tissue of a plant, the method including the step of bringing a solution for florigen introduction containing a florigen and a cell-penetrating peptide in one solvent into contact with a shoot apical tissue of a plant. The driving device is disposed on a bottom of a concave formed between the light-emitting device and the light-receiving device so that the driving device is lower than a straight line connecting a backward light emitting point of the light-emitting device and a backward light receiving point of the light-receiving device. An electric powered winch can be attached to the boom receiver.