A system for growing a plant (1) in an at least partly conditioned environment includes a cultivation base (11) for receiving a culture substrate (3) with a root system (4) of the plant therein. Root temperature control elements (12) are provided which are able and adapted to impose a predetermined root temperature on the root system, and lighting elements (20,21,22) which are able and adapted to expose leaves of the plant to actinic artificial light. Leaf heating elements are also provided, which are able and adapted to impose on the leaf of the plant a leaf temperature varying from an ambient temperature. In a method for growing the plant a carbon dioxide assimilation management of a leaf system of the plant is thus influenced, and a supply of actinic light, the root temperature and the carbon dioxide assimilation management are adapted to each other.