Mushroom Cultivation: An Easy Guide To Growing Mushrooms

Mushrooms are fungi and require different conditions to grow than plants. They are grown in highly controlled environments and have a fast growth rate, doubling in size in 24 hours. The growing cycle for mushrooms is six weeks, with the first three weeks spent growing the vegetative part of the fungus, called the mycelium. The last three weeks are spent picking mushrooms and letting them grow again. Mushrooms can be grown on logs or in bags, beds, or containers filled with sterilized sawdust and wood chips or compost. The ideal growing conditions for mushrooms are around 70 degrees Fahrenheit and greater than 90% humidity.

Mushrooms require sterile conditions to grow and the process often begins in a laboratory

Mushrooms are cultivated in a highly controlled environment, and the entire process begins in a laboratory to ensure sterile conditions. The spores, or natural seeds of the mushroom, are too tiny for human handling, so lab personnel inoculate and incubate sterile cereal grains with the spores. These grains then become "spawn", which can be sown like seeds.

The grower then prepares the mushroom substrate, or growing medium, which is key to mushroom production. The substrate is a source of bacteria and must be pasteurised or sterilised before use to prevent contamination. Pasteurisation involves heating the substrate to between 65 and 85°C for 1.5 to 2 hours, reducing the number of competing organisms. Sterilisation, on the other hand, kills all bacteria and pathogens by heating the substrate to temperatures above 120°C under pressure. The choice between pasteurisation and sterilisation depends on the substrate variety and its nutrient level. For example, manure-based substrates, which are already teeming with germs and microbial life, must always be sterilised.

Coffee grounds are an exception to the rule and do not require pasteurisation or sterilisation if they are used quickly and handled with proper hygiene. This is because the brewing process pasteurises the grounds.

The prepared substrate is then used to grow the mushrooms. The ideal growing conditions for mushrooms are around 70°F and greater than 90% humidity. Natural logs, such as oak and maple, work well as a growing medium, especially if they are newly cut and have not dried out. Synthetic logs, made from bagged mixes of sawdust, millet, rye, and water, are also used to feed the mycelium.

Specialty mushrooms like Shiitake and Oyster are grown on logs or in bags

Specialty mushrooms, such as Shiitake and Oyster, are cultivated differently from common white and brown button mushrooms. These mushrooms are typically grown on logs or in bags, with the process varying slightly depending on the chosen method.

When growing specialty mushrooms on logs, the first step is log selection, ensuring the correct types of wood are chosen as different trees support different mushrooms. Live trees are preferred, and oaks and maples are considered the best hosts as they are dense and provide ample nutrition for sustained fruiting. After selecting the logs, they are cut to a length of approximately four feet during the dormant season and aged for up to two weeks. Next, one-inch-deep holes are drilled into the logs on all sides, staggered and spaced about four to six inches apart to provide ample room for the mushrooms to grow. The spawn, which consists of sawdust colonized by the spores of the specific mushroom type, is then inserted into these holes. The logs are propped on end and placed side-by-side in a shady area to prevent drying. It can take between three months and a year for the mushrooms to begin growing, but once established, they produce multiple flushes per year.

Alternatively, specialty mushrooms can also be grown in bags. This method involves using synthetic logs or blocks made of bagged mixes of sawdust, millet, rye, and water to nourish the mycelium. Similar to log cultivation, the spawn is introduced into the growing medium, providing the necessary conditions for mushroom growth. Bag cultivation offers faster results and year-round growing in a controlled habitat, making it a preferred choice for commercial purposes.

The choice between log and bag cultivation depends on the specific mushroom species and the resources available. For example, while Shiitake mushrooms can be grown successfully on both hardwood logs and sawdust blocks, commercial growers often prefer the latter due to their quicker turnaround time. On the other hand, Oyster mushrooms can be grown in bags or logs, but logs are recommended for their long-term harvest potential.

Overall, the growth of specialty mushrooms like Shiitake and Oyster involves unique processes that differ from those of common mushrooms, requiring careful selection of growing mediums and controlled conditions to ensure optimal development and yield.

Mushrooms grow well in substrates rich in organic material, like compost

Mushrooms are fungi, and unlike plants, they require different conditions to grow. Fungi grow well in substrates rich in organic material, like compost. The substrate is a key ingredient in mushroom production. The two types of starting material used for mushroom substrate are: synthetic compost consisting of wheat or rye straw, hay, crushed corn cobs, cottonseed meal, cocoa shells, and gypsum; or manure-based compost 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.

In the growing house, the pasteurized substrate is placed in stacked wooden trays or beds, and the spawn (the "seeds" of the mushroom) is mixed in. A top layer, usually of peat moss, is then applied. From this point, it takes about three weeks to produce the first mushrooms for harvest. Throughout the growing period, temperature and humidity are carefully controlled. Mushrooms mature at varying times, so picking by hand is continuous for two to three weeks. Every mushroom is harvested by hand.

The ideal growing conditions for mushrooms are around 70 degrees Fahrenheit and greater than 90% humidity. Natural logs work well, and oaks and maples serve as the best hosts. For natural logs, it is best if the log is newly cut so that it hasn't dried out. Synthetic logs are just bagged mixes of sawdust, millet, rye, and water to keep feeding the mycelium. Logs provide a growing medium that is naturally sterile and, when responsibly sourced, is also sustainable and self-replenishing.

Mushrooms grow from spores or tissue culture. Every mushroom releases thousands of spores into its environment, each carrying unique genetics. Growing from spores is unpredictable, and none will be identical to its "parent". Some mushrooms grow from spores that are produced internally, within sac-like cells called asci. When one of these spores lands in the right environment, it will germinate and send out a small filamentous thread called a hypha. These fungi grow from the tip of the hypha, extending forward in response to outside stimuli. While scientists don't fully understand this process, the dominant theory is that an organelle called the Spitzenkorper organises and directs the growth patterns in pulses, like a microscopic architect.

The growing cycle for mushrooms is six weeks, with the last three weeks spent picking mushrooms

Mushrooms are fungi and require different conditions to grow than plants. They can be grown in a variety of settings, from warehouses to basements, as they do not require sunlight. The most common method for growing mushrooms is inside large plastic bags filled with sterilized sawdust and wood chips. This method helps replicate the natural conditions that mushrooms need to grow, such as adequate moisture, proper temperature, and limited light.

Specialty mushrooms like Shiitake, Oyster, and Maiitake are grown differently from common white and brown button mushrooms. They are typically grown in bottles, on logs, or in containers filled with sawdust. The logs can be natural or synthetic. Natural logs, such as oaks and maples, work well as hosts for mushrooms. Synthetic logs are bagged mixes of sawdust, millet, rye, and water. The ideal growing conditions for mushrooms are around 70 degrees Fahrenheit and greater than 90% humidity.

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. During this time, the mycelium colonizes the casing layer, a key ingredient in mushroom production. The temperature in the growing room is maintained above 20 degrees Celsius to allow the mycelium to develop fully.

In the last three weeks of the cycle, the temperature is dropped below 20 degrees Celsius to signal the spawn to develop a fruit body (mushroom) and drop the spores necessary for reproduction. Mushrooms are then harvested by hand and left to rest for a few days, after which they grow back and can be picked again. This process allows for the year-round production of mushrooms.

Mushrooms are harvested in stages and are left to rest for three days between flushes

Mushrooms are unique organisms that require specific conditions to grow. They are not plants or animals but belong to the kingdom of fungi, with up to 12 million diverse species. The common mushrooms we see, with their iconic caps and stems, are part of the Basidiomycota phylum. These mushrooms produce spores outside of club-like cells called basidia, and each spore carries unique genetic information.

The cultivation of mushrooms involves creating the ideal conditions for growth, which differ from those of plants. The growing process often begins in a laboratory, where tiny spores are inoculated onto sterile cereal grains. These grains, called "spawn," are then sown into a substrate, the basic growing medium. The substrate consists of synthetic compost made from plant and animal products or manure-based compost. This process provides the necessary decayed organic matter for mushroom growth.

Once the substrate is ready, it is placed in stacked wooden trays or beds in the growing house. The spawn is mixed in, and a top layer, usually peat moss, is applied. The ideal temperature is maintained at around 70 degrees Fahrenheit, and humidity is kept above 90%. These controlled conditions are crucial for mushroom growth. It takes about three weeks for the first mushrooms to be ready for harvest.

Mushrooms mature at different rates, so harvesting is a continuous process that can last for two to three weeks. Each mushroom is carefully picked by hand. After harvesting, the entire growing area is pasteurized to prepare for the next crop. This process ensures that any remaining spores and mycelium can develop into new mushrooms.

The harvested mushrooms are then sent to a packinghouse for sorting, weighing, packing, and shipping. The rest period of three days between flushes allows for new mushrooms to develop and ensures a continuous supply for the next harvest. This staged harvesting method optimizes mushroom production and maintains the quality of the crop.

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