Spawning : For spawn run air temperature of 23° ± 1C is maintained in the room, with corresponding bed temperature of 24-25°C (1-2°C higher than air temperature). The fresh air valve is closed and entire air is re-circulated, allowing the carbon dioxide to accumulate to the level of 15000 ppm, desirable for quick spawn run. Higher concentration of CO2 accelerates the spawn run/vegetative growth of the mushroom fungus. During spawn run above temperature has to be maintained, till entire compost is impregnated with the mushroom mycelium, alongwith other parameters like high CO2 concentration, high RH (will be discussed later). Increase or decrease in temperature effects the CO2 production of the compost and the RH of the room. With increase in temperature, RH will tend to fall, and with decrease in tempt. RH will increase. The properly insulated room will ensure uniform temperature in the cropping room at every stage of crop growth. The air will go into the room at the will of the grower and as per requirement inside, suiting the crop stage. The heat from the cropping room is removed via cooling coils in the AHU.
Casing : The environmental conditions suitable for spawn run, are suitable for case run as well. The same conditions will be provided for 7 days for case run, as for spawn run, i.e., temperature of 23°C in the air and 24°C in the bed. The RH/CO2 will be same as required for spawn run. Within one week the case run will be completed, and case run is completed the moment the mycelium is observed in the valleys. Valleys are areas between the peaks as can be seen on top of casing. Casing is applied uniformly and the material used should not be a finely ground casing soil but in the form of small clods, which form valleys/peaks on surface of casing. The CO2 conc. and RH should also be within the optimum range for effective/quick case run.