How to Grow Mushrooms in Cow Dung

Gather the cow manure. Avoid areas of your barn or pasture that contain standing water. Fill a bucket about halfway with manure and combine with equal amounts of soil and fresh straw. Mix these ingredients together in a dry area of your yard. Lightly spray a fine mist of water over the mixture. About an inch of water will make the mixture evenly damp. Heap the mixed ingredients into a small pile and allow it to rest until the temperature inside your pile reaches about 130 degrees Fahrenheit. Let the pile rest for three or four days once the temperature reaches this level, the warmth will destroy harmful bacteria and weed seeds.

Turn your small compost pile once every two to three days, moving the inside sections toward the outside and the bottom of the pile to the top. Mist your pile with a sprinkling of water after you turn the materials.The manure will be ready to use in your mushroom garden as soon as the pile decomposes into a fine, crumbly mixture. This process may take several months to a year.

Spread a 2-inch-deep layer of the composted cow manure into the bottom of a large, flat container. A storage bin, casserole dish or other waterproof container will work for this purpose. Evenly sprinkle mushroom spores over the top of your manure compost. Lightly spray the surface until it becomes evenly damp.

Place a piece of plastic wrap over the top of your container. Use the tip of a sharp knife to poke small holes in the plastic wrap every couple of inches. Place the container in a dark room or closet to allow the spores to germinate and grow. Mist the mushrooms every three or four days to keep the soil slightly moist.

Look for your small mushrooms to begin appearing during the first two weeks, maturing to provide your initial harvest about three weeks after planting. Your fresh mushroom harvest can continue for a period of up to eight weeks.