Agaricus bisporus - Button mushroom

Button mushroom (Agaricus bisporus) is the world’s most widely cultivated mushroom, grown on composted straw/manure substrate under a casing layer; white, cremini, and portobello are the same species sold at different stages of maturity.¹

Inputs

• Compost substrate: composted wheat straw, hay, or horse manure, supplemented with a nitrogen source (poultry manure, cottonseed meal) and 70-100 lbs gypsum per ton of dry ingredients; composted (Phase I) 3-15 days, then pasteurized at 140°F (60°C) for at least 2 hours and finished (Phase II) over 7-18 days total.¹
• Spawn run: grain spawn incubated in the substrate at 75-77°F (24-25°C), high humidity, for 14-21 days.¹
• Casing layer: limed sphagnum peat moss (or pasteurized clay loam/coir) spread over the spawn-run substrate.¹
• Fruiting (cropping): air temperature 60-66°F (15-17°C), high humidity, CO2 held to 1,000-2,500 ppm; first harvest 15-21 days after casing, with 3-4 flushes on a 7-10 day cycle.¹

Outputs

• Human food¹
• Compost: spent substrate, weathered 6 months or more, usable as a garden soil amendment.¹

Type

• Edible fungi

Footnotes

1. Basic Procedures for Agaricus Mushroom Growing | Penn State Extension ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷