What yield of button mushroom can I expect per kg of compost?

Button mushroom yield is usually measured as biological efficiency, which is fresh mushroom weight against compost weight. With good pasteurised compost, quality spawn and proper temperature, growers commonly get in the broad range of 15 to 25 kg of fresh mushroom per 100 kg of wet compost, spread over two to three main flushes in roughly 6 to 8 weeks of cropping. Beginners often get less in the first crop because of temperature and contamination issues, so plan conservatively. The compost recipe, casing and how steady you keep the climate make a big difference. Treat these as a planning range, not a promise, and confirm realistic local figures with growers near you and your KVK or DMR Solan before you scale.