Oyster mushrooms grow naturally on every continent. They grow on almost anything that contains cellulose or lignin. More than 50 varieties are grown commercially. 21‐29 C Temperature <1,000 ppm CO2 90‐95% Relative Humidity 500‐1000 Lux P. citrinopileatus (Golden Oyster Mushroom) Pink oyster mushroom growing on rice straw. 20‐30 C temperature 500‐1500 ppm CO2 85‐90% Relative Humidity 750‐1500 Lux light Oyster mushroom growing on barley straw Oyster mushroom grows on wheat straw.