What we do

Elf Farm Supplies produces mushroom compost (substrate), and has certification to do this organically.

Our mushroom compost is manufactured from recycled agricultural materials, including wheaten straw, poultry manure, stable bedding, gypsum and other nitrogen rich products, which are combined with a well-engineered environment to produce a high quality product.

The compost production process

Compost production is a four stage process, which involves:


  • Straw bales are pre-wet and allowed to heat up to remove the waxy layer from the straw and to initiate the composting process
  • After straw bale wetting, the bales are transferred into the pre-wet shed, where they are broken up and mixed with other ingredients using a mobile blender. Water is also added through this mixing process
  • This material is piled together (the piles are known as ‘ricks’) and turned and blended. Water is also added to further promote the composting process over the following days
  • Fresh air is supplied through air pipes underneath the ricks to keep the process aerobic

Phase 1

  • The material is then moved into the phase 1 tunnels
  • As in the pre-wet shed, fresh air is supplied through air pipes underneath the bunkers to control compost temperatures and oxygen levels, and keep the process aerobic
  • The compost is blended a number of times and has water added to adjust its moisture content.

Phase 2

Both phase 2 and 3 of the compost process involves the compost being stored in tunnels which are designed to enable the circulation of air through the compost.

  • Phase one compost is loaded into tunnels using a cassette filler which is a system of conveyors that extend into the tunnels
  • The compost is placed on top of a pulling net, which enables subsequent removal from the tunnel
  • Each tunnel holds up to 200 tonnes of phase one compost that will finally reduce to 115 tonnes of phase three compost
  • The phase 2 process is computer controlled using fresh and recirculated air to control compost temperatures and oxygen levels
  • Each tunnel has a dedicated air intake and fan system. Air is passed through a series of filters to remove particles down to four microns absolute. Filtration is important to prevent the introduction of competitor species
  • Phase 2 and 3 is serviced with chillers and cooling towers which supply 2700kW of cooling capacity
  • Compost is initially levelled to a consistent temperature then heated for eight hours to pasteurise the compost. Phase two is designed to kill unwanted pathogens and to create an ideal nutrient and bio-logical medium for mycelium development (from which mushrooms grow)
  • After pasteurisation, the compost is conditioned at 45 to 50 degrees Celsius for three to four days.

Phase 3

After phase 2 is complete, the compost is cooled down to 25 degrees Celsius, and mushroom spawn is added to the compost (phase 3). This operation is undertaken following intensive cleaning and disinfecting. It is imperative that “sterile” conditions are created to prevent infection of the compost with unwanted pathogens that can impede mushroom growth.

  • Phase 2 material is removed from the tunnel using a pulling winch, inoculated with spawn and returned to another tunnel using a cassette filler.
  • The phase 3 process is fully computer controlled to create environmental and biological conditions that maximise mushroom mycelium development.
  • At the end of this process, phase three material is removed from the tunnels using a pulling winch, loading the compost onto trucks for bulk shipment.

Phase 3 blocks

At the end of the process, some of the phase 3 compost is then manufactured into blocks for shipment.

The length of the process from commencement of pre-wet to ship out is approximately six to seven weeks. Mushroom harvesting then commences a further two weeks after delivery of the material to the farm.