A method of controlling an environmental control system (11-13) in a plant growing environment, said method comprising; - selecting a grow protocol from a collection of grow protocols stored in a memory; - selecting a container identifier identifying a container from a plurality of container identifiers, said container comprising at least one plant and said plurality of container identifiers being stored in said memory or in a further memory; - associating said grow protocol with said container identifier, said grow protocol comprising one or more target values for one or more growth condition parameters; - determining an adjusted target value by applying an adjustment to a target value of said one or more target values for a first growth condition parameter of said one or more growth condition parameters, said adjustment being larger than a predetermined minimum and smaller than a predetermined maximum; - controlling an environmental control system (11-13) based on said adjusted target value; - obtaining measurement information associated with said container identifier from at least one device (21-23); - determining a measured plant growth parameter value based on said measurement information; - comparing said measured plant growth parameter value with an expected plant growth parameter value, said expected plant growth parameter value being included in said grow protocol; - determining a merit related to a difference between said measured plant growth parameter value and said expected plant growth parameter value; - replacing , in said grow protocol, said target value with said adjusted target value in dependence on said merit exceeding a threshold; and - replacing , in said grow protocol, said expected plant growth parameter value with said measured plant growth parameter value in dependence on said merit exceeding said threshold. - selecting a grow protocol from a collection of grow protocols stored in a memory; - selecting a container identifier identifying a container from a plurality of container identifiers, said container comprising at least one plant and said plurality of container identifiers being stored in said memory or in a further memory; - associating said grow protocol with said container identifier, said grow protocol comprising one or more target values for one or more growth condition parameters; - determining an adjusted target value by applying an adjustment to a target value of said one or more target values for a first growth condition parameter of said one or more growth condition parameters, said adjustment being larger than a predetermined minimum and smaller than a predetermined maximum; - controlling an environmental control system (11-13) based on said adjusted target value; - obtaining measurement information associated with said container identifier from at least one device (21-23); - determining a measured plant growth parameter value based on said measurement information; - comparing said measured plant growth parameter value with an expected plant growth parameter value, said expected plant growth parameter value being included in said grow protocol; - determining a merit related to a difference between said measured plant growth parameter value and said expected plant growth parameter value; - replacing , in said grow protocol, said target value with said adjusted target value in dependence on said merit exceeding a threshold; and - replacing , in said grow protocol, said expected plant growth parameter value with said measured plant growth parameter value in dependence on said merit exceeding said threshold. <EOS>