Mushrooms are extremely fast-growing and Arrold’s company, Li-Sun Exotic Mushrooms, produces 1500 kilograms of them every week.
Exotic mushrooms grow naturally on decaying trees in forests. In a controlled environment they are cultivated on sawdust or other plant materials such as straw or cottonseed. At Li-Sun the sawdust is mixed with wheat, rice bran, lime and gypsum, placed in bags or bottles and sterilised at 120°C for two hours to eliminate any organisms present. When the sawdust has cooled a pure culture of the mushroom is added and the bags or bottles incubated at 22°C. The incubation period is anywhere from three to ten weeks, depending on the species.
After this incubation period the crop is taken to the tunnel and the plastic bags removed to allow for cropping. The combination of watering the crop and the warm, humid conditions in the tunnel promotes growth and within five days mature mushrooms appear. The inoculated sawdust will continue to fruit for several weeks before the mushroom culture is exhausted.
Oyster and shimeji mushrooms are grown on pasteurised cottonseed hulls and wheat straw that has been steamed at 70°C. This mix goes into bags with holes punched in them through which the mushrooms will grow.
Staff move through the tunnel daily, picking mushrooms, watering the bags and soaking the sawdust blocks in water. Once the mushrooms are harvested they are returned to the laboratory where they are packaged and sent directly to produce markets around Australia.
The tunnel evokes distant
childhood memories of demons
and leprechauns emerging from
the murky gloom.