Richters InfoSheet D3845  

Maitake Mushroom Kit Growing Instructions

The maitake mushroom is quite fastidious in its environmental requirements, and takes careful attention to be successful with. Ideal conditions are a shaded, but not dark place with a cool temperature of 13-18 degrees Celsius (55-65 degrees Fahrenheit), and 80-90% relative humidity.. Choose a relatively clean place to grow your maitake. Dirty environments will have mould spores, mites and insects which may contaminate your plant and damage it. Since the maitake is relatively slow growing, it is more susceptible to contaminate than the Reishi and Shiitake mushrooms for example.

The maitake grows quite slowly at optimal temps, and under most circumstances it is best to leave the mushroom plant in the special polypropylene autoclave bag in which you receive it.

Pull the top of the bag up like a tent over the substrate block, but do not remove the twist tie at the top of the bag. The maitake will “pin” (start to form mushrooms) most readily at a temperature of about 15-18 degrees C (60-65 degrees F). Pinning will be slower at temperatures cooler than 55 degrees F (13 degrees C) and may not occur at all at above 65 degrees F (18 degrees C). Pinning will usually occur on the top of the substrate block in response to the slight increase in ventilation which occurs when the top of the bag is pulled up in tent fashion, but may occur on the sides of the block if there are slits or holes there. It may take a month or so for a mound of dark coloured primordia (pins) to form. After pinning, the growing mushrooms will tolerate a slightly wider temperature range.

Since the mushroom is slow growing it will tend to dry out if the top of the bag is opened too much and too early. Once a mound of primordia has formed, loosen the tie on the top of the bag a little at a time to provide increasing ventilation and more room for the mushroom to grow. Watch for any signs of drying out and reduce ventilation if necessary, or increase the humidity in the greater environment to compensate. As the mushrooms expand loosen the tie more and more. Eventually remove the tie when the growing mound of mushrooms starts to fill the head space of the bag. As the mushrooms fill the head space, gradually pull the mouth of the bag open, a little at a time, and eventually slit the top part of the bag, and then pull the sides of the bag away from the growing mushrooms. As you open up the bag, humidity control becomes critical.

Maitake are slow growing and are very susceptible to drying out if the humidity is low. Although high humidity is essential, the mushrooms do not like to be wet for more than a short time. They may succumb to bacteria if wet for more than an hour or two at a time. As a method of keeping your mushrooms humid, frequent misting directly onto them is not a very satisfactory approach and often leads to bacterial problems. A large clear plastic bag or poly sheet over wire or a 1 inch by 2 inch frame placed over the top may serve as a humidity tent.

During wet, mid weather, a protected outdoor environment may be a good place to let your mushrooms mature. Indoors, during dry weather, or in dry climates, it will be necessary to provide extra humidity by placing a moist cloth inside the enclosure or misting the inside of the tent. The humidity in a room with a damp concrete floor will usually be pretty high, especially near the floor.

During warm weather, mushroom flies can be a problem. A partial solution to this is to scrape off any patches in which the larvae are observed.


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D3845   ©2000 Otto Richter and Sons Limited


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