I picked up six bags of mushroom compost at a local sale yesterday, and have noticed a gassy smell from them. I suspect this is methane arising from anaerobic decomposition. Apart from concern about contributing further to climate change (!), what should I do with this material? An earlier forum message suggests it might be acidic, and that I should mix it into my existing compost pile. Thank you in advance for any suggestions or advice.
I would agree that the bagged Spent Mushroom Substrate (SMS) has become anaerobic. Just pile it up and turn it to get oxygen into the material so that the aerobic organisms will again predominate. The sweeter smell should tell you when it's ready to use. It is very unlikely that the SMS has become acidic just by being bagged. Commercially grown mushrooms prefer an alkaline medium.
