Abstract: A composting plant and method for composting organic waste such as household waste separated at the source, sludge, wood chippings, straw, farmyard manure. The plant comprises a sealed compartment with an inlet zone with a device for feeding in the waste which is advanced from a receiving and preprocessing plant through an airtight sluice device; a process zone with one or more devices preferably a texturing agitator (14) suspended in a runner (46) for advancing and aerating of the waste from the inlet zone and through the process zone to an outlet zone with devices (18) for discharging the composted waste from the compartment. The bottom of the process zone which is connected to a ventilating equipment (26, 30, 34) is designed in such a manner that an aeration takes place up through the waste heap preferably via a bottom layer of coarse organic material such as wood chippings.