To provide a growth controlling system for a plant capable of readily and rapidly knowing growth conditions of the plant and the application amount, etc., of a chemical for promoting the growth thereof and adopting right measures for the growth of the plant even by an amateur without experience in growth of the objective plant.

This growth controlling system 10 for the plant is composed so as to include a step of detecting physiological information about the plant and a step of detecting the state of soil where the plant takes roots in a growth site 12 of the plant, a step of transmitting the detected physiological data and soil state data to a control center 18 separate from the growth site 12, a step of diagnosing the growth conditions of the plant based on the received data and determining the necessary application amount of the chemical in the control center 18 and a step of feeding back the determined application amount of the chemical from the control center 18 to an applier in the growth site 2 of the plant.