Mushroom Cultivation: A Step-By-Step Guide To Growing Mushrooms

Mushrooms are fungi and require very different conditions to grow than plants. They are grown in highly controlled environments, typically in large plastic bags filled with sterilized sawdust and wood chips, or on natural or synthetic logs. The ideal growing conditions for mushrooms are around 70 degrees Fahrenheit and greater than 90% humidity. The growing cycle for mushrooms is six weeks, with the first three weeks spent growing the vegetative part of the fungus, and the last three weeks spent picking mushrooms and letting them grow again.

Mushrooms are fungi, not plants

The first step in mushroom cultivation is to create a sterile environment, as mushrooms are very sensitive to their surroundings. The process often begins in a laboratory, where spores, or natural seeds, are inoculated onto sterile grains and incubated. These grains then become "spawn", which can be sown. The grower then prepares the substrate, or growing medium, which is a key ingredient in mushroom production. This substrate is typically a mixture of decayed organic matter, such as compost or sterilised sawdust and wood chips.

The next stage is colonisation, where the mycelium, or vegetative part of the fungus, grows and spreads through the substrate. This process takes around three weeks. The final stage is fruiting, where environmental adjustments trigger mushroom development. A drop in temperature signals the spawn to develop a fruit body (the mushroom) and release spores. Mushrooms can be harvested in stages and left to regrow.

Specialty mushrooms like Shiitake, Oyster, and Maiitake are often grown on logs or in bottles and containers. The logs can be natural, such as oak or maple, or synthetic, made from bagged mixes of sawdust, millet, rye and water. The ideal growing conditions for mushrooms are around 70 degrees Fahrenheit and greater than 90% humidity.

Mushrooms have a fast growth rate, doubling in size in 24 hours. They can be grown year-round and are typically harvested by hand.

They require sterile conditions

Mushrooms are fungi and require entirely different conditions to grow than plants. They are the fruiting bodies of fungi, thriving on substrates rich in organic material. As such, they require sterile conditions, and the entire growing process begins in a laboratory. The spores, or natural seeds of the mushroom, are too tiny for human handling. Therefore, lab personnel will inoculate sterile cereal grains with the spores and incubate them until they develop into a viable product. These grains become "spawn", which can then be sown like a seed.

The grower then prepares the basic growing medium for mushroom production, called the substrate. This is a key ingredient in mushroom production and typically involves a synthetic compost consisting of wheat or rye straw, hay, crushed corn cobs, cottonseed meal, cocoa shells, and gypsum. Alternatively, a manure-based compost can be used, made from stable bedding from horse stables or poultry litter. This process converts plant and animal products into a mixture of decayed organic matter that is necessary for growing mushrooms.

Specialty mushrooms like Shiitake, Oyster, Maiitake, and Enoki are often grown differently, for example in bottles, on logs, or in containers filled with sawdust. Natural logs work well, and oaks and maples serve as the best hosts. For natural logs, it is best to use newly cut wood so that it hasn't dried out. Synthetic logs are just bagged mixes of sawdust, millet, rye, and water to keep feeding the mycelium.

The growing cycle for mushrooms is six weeks. The first three weeks are spent growing the vegetative part of the fungus, called the mycelium, which is similar to the roots of a plant. The temperature in the growing room is then dropped below 20 degrees Celsius, signalling the spawn to develop a fruit body (mushroom) and to drop the spores that are in the gills underneath the mushroom cap. This is the reproductive mechanism for another mushroom to grow and allows for year-round production.

They grow in substrates rich in organic material

Mushrooms are fungi and require different conditions to grow than plants. They are the fruiting bodies of fungi, and they thrive on substrates rich in organic material. Mushrooms require adequate moisture, proper temperature, and limited light. By replicating their natural habitat, various species can be cultivated successfully.

The first step in cultivating mushrooms is inoculation, which involves introducing mushroom spores or mycelium to a suitable substrate. The mycelium, or spawn, is placed inside a growing medium, such as natural logs or synthetic mixes of sawdust, millet, rye, and water. The ideal temperature for mushroom growth is around 70 degrees Fahrenheit, with humidity greater than 90%.

The next step is colonization, where the mycelium is allowed to permeate the substrate fully. This step takes about three weeks, during which the mycelium grows and colonizes the casing layer.

After colonization, fruiting is triggered through environmental adjustments. The temperature in the growing room is dropped below 20 degrees Celsius, signalling the spawn to develop a fruit body (mushroom) and release spores.

Finally, mature mushrooms are harvested at the optimal time, typically after four days of growth. Mushrooms can be grown year-round and are harvested in stages or flushes, with the first flush lasting about four to five days, followed by a three-day rest period.

They can be grown on logs or in bags

Mushrooms can be grown on logs or in bags. The process of inoculating logs requires mycelium (spawn) to be placed inside the growing medium, whether natural or synthetic, and then climate-controlled. Natural logs work well, and oaks and maples serve as the best hosts. For natural logs, it is best to use freshly cut logs so that they haven't dried out. Synthetic logs are bagged mixes of sawdust, millet, rye, and water to keep feeding the mycelium.

When growing mushrooms on logs, the first step is to drill a series of small holes into each log. Each hole is then tightly packed with spawn and covered with wax to ensure optimal mycelium-growing conditions and reduce contamination by other fungi species. The number of holes drilled depends on the diameter of the log. A general rule of thumb is to have as many rows of drill holes as there are inches of diameter. For example, a log with a 6-inch diameter needs 6 rows with a minimum of 30-40 drill holes. The holes should be staggered in a diamond pattern to ensure rapid growth of the fungus throughout the log.

There are two types of spawn commonly used for growing mushrooms on logs: plug spawn and sawdust spawn. Plug spawn is ideal for smaller projects or if you don't want to invest in equipment. Sawdust spawn colonizes about 30% faster than plugs but requires additional tools. One 5lb bag will inoculate between 10-40 logs.

Mushroom grow bags are a popular method for cultivating mushrooms due to their simplicity, cost-effectiveness, and efficiency. They are made from high-grade polypropylene plastic that can withstand high sterilization temperatures. They come in various sizes and are equipped with a filter patch to allow for fresh air exchange while keeping contaminants out. The transparency of the bags allows for easy monitoring of mushroom growth without opening the bag, further reducing the risk of contamination.

To use a mushroom grow bag, the substrate or growing medium, such as grain, straw, or wood chips, is prepared and sterilized before being placed inside the bag. Mushroom spawn is then added to inoculate the bag, which is then sealed and placed in a conducive environment for the mycelium to colonize the substrate. Once fully colonized, the bag is exposed to fresh air and light to initiate fruiting conditions. Some growers cut holes in the bag to allow mushrooms to grow out from various directions.

They have a six-week growing cycle

Mushrooms are fungi and require different conditions to grow than plants. They have a fast growth rate, doubling in size in 24 hours, and can be grown year-round. The growing cycle for mushrooms is six weeks.

The first three weeks of the six-week cycle are spent growing the vegetative part of the fungus, called the mycelium. This is similar to the roots of a plant and is also called colonizing the casing layer. The growing environment must be carefully controlled, with the ideal temperature for mushrooms being around 70 degrees Fahrenheit and greater than 90% humidity.

During the first three weeks, the spores or natural seeds of the mushroom are inoculated into a suitable substrate or growing medium. This substrate is typically a mixture of decayed organic matter, such as synthetic compost made from wheat or rye straw, hay, crushed corn cobs, cottonseed meal, cocoa shells, and gypsum, or manure-based compost. The mycelium is allowed to permeate the substrate fully during this time.

In the last three weeks of the cycle, the temperature in the growing room is dropped below 20 degrees Celsius. This temperature change signals the spawn to develop a fruit body (the mushroom) and to drop the spores that are in the gills underneath the mushroom cap. This is the reproductive mechanism for another mushroom to grow and allows for year-round production. The mushrooms are then harvested in stages or flushes, with the first flush being harvested over four or five days, followed by a three-day rest period.

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