A multi-level horizontal air flow distribution system is provided. The air flow distribution system includes a multi-level rack, an air exchange unit, an air delivery structure and an air exhaust structure. The air exchange unit includes a blower that blows air into the air delivery structure. The air delivery structure delivers directed streams of cold air in between plants and lights supported by the multi level rack. The cold air pushes warm air produced by the lights out of the multi-level rack. The warm air rises into the air exhaust structure and may be directed to the air exchange unit to be recycled within the air flow distribution system.
