Select a cultivation site that is in full shade. Dig a bed 2 1/2 feet square and 6 inches deep. Cover the bottom of the bed with a layer of cardboard.
Soak 30 lbs. of wood chips in water overnight. Pour the wood chips through a large sieve to drain the water. Pour half the wet chips into the bed and spread them flat.
Pour the mushroom spawn evenly over the wet wood chips. Cover the spawn with the rest of the wood chips and rake them into an even layer.
Cover the wet wood chips with a 2-inch layer of straw. Water the straw until it is damp. Continue watering daily, or whenever the bed feels dry to the touch.
Cover the bed with a 2-inch layer of bark mulch in the fall to protect the spores from frost. Uncover the bed in spring.