A Detailed Guide to Oyster Mushroom Cultivation Techniques and Management Methods

The oyster mushroom (Pleurotus ostreatus), also known as the abalone mushroom, tree oyster mushroom, oyster cap, and black peony mushroom, and called xiu zhen gu in Taiwan, China, is a species in the family Pleurotaceae, order Agaricales, phylum Basidiomycota, and is a fairly common gray edible mushroom.

Building the Mushroom House

An existing empty room, basement, or similar space can be converted into a mushroom house. If conditions permit, a new mushroom house can also be built. The mushroom house should face south, be located on high ground, be close to a water source, and have convenient drainage. A mushroom house with an indoor cultivation area of 20 sq m is appropriate. The roof and walls should be thick, and the doors and windows should be arranged reasonably to help with heat retention, moisture retention, ventilation, and light transmission. The interior walls and floor are best whitewashed with lime and smoothed with cement for easy disinfection. In addition, a simple mushroom house can be built, namely a semi-underground mushroom house 1.5-2.0 m below ground level. To make full use of the space in the mushroom house, bed frames can also be set up inside for cultivation. The bed frames are arranged north to south, should not lean against the walls on any side, and should have a 60 cm wide walkway between them. The bed surfaces of the upper and lower tiers should be 50 cm apart, with the lower tier 20 cm above the ground, and the upper tier should not exceed the windows so as not to affect light. The bed surface should be no more than 1 m wide for easy management. The bed surface is laid with wooden boards, bamboo poles, or straw mats. 

Disinfecting the Mushroom House

The mushroom house must be disinfected before use, and old mushroom houses in particular must be thoroughly disinfected. This reduces contamination by competing microorganisms and the occurrence of insect pests.

The disinfection methods are as follows:

(1) For a 100 cubic meter mushroom house, use 1 kg of formaldehyde and 0.5 kg of potassium permanganate, heat them, and fumigate with the house sealed for 24 hours.

(2) Spray with a 5% carbolic acid solution.

(3) Spray with an 800-fold dilution of dichlorvos.

Preparing the Substrate

Materials such as sawdust, cottonseed hulls, waste cotton, rice straw, sugarcane bagasse, corncobs, corn stalks, peanut shells, and soybean stalk powder can all be used to cultivate oyster mushrooms, either singly or in combination. However, to achieve high-yield, high-quality cultivation results, appropriate amounts of auxiliary materials such as wheat bran, rice bran, gypsum, and superphosphate should be added. Below are several commonly used formulas and their preparation methods.

(1) 99% cottonseed hulls, 1% lime. Dissolve the lime in an appropriate amount of water, sprinkle it evenly over the cottonseed hulls, and while sprinkling water, tread, and turn the mixture until the cottonseed hulls have an appropriate and uniform moisture content.

(2) 99% rice straw, 1% lime. Cut the rice straw into pieces about 5 cm long, soak them in 1% lime water for 5-6 hours, then remove them once they have absorbed enough water, drain them, and they are ready for pressing into molds and spawning.

(3) 89% sawdust, 1% lime, 10% wheat bran. Mix the dry ingredients, add water, and turn to mix evenly until the moisture content is about 60%.

(4) 90% corncob powder, 9% rice bran, 1% lime. Mix the dry ingredients, add water, and turn to mix evenly until the moisture content is appropriate.

(5) Corncobs or corn stalks: crush the raw material, soak it in clean water or 1% lime water for 1-2 days, then remove it once it has fully absorbed water, drain it, and it can be spread flat to form a mushroom bed and spawned in layers.

(6) 78% peanut shells and peanut stalks, 20% bran, 1% gypsum, 1% sugar. First sun-dry and crush the peanut shells and peanut stalks, dissolve the sugar in a small amount of water and mix it with the dry ingredients, then add clean water and mix evenly until the moisture content is about 58%.

(7) 50-69% sugarcane bagasse, 30-49% sawdust, 1% lime. First mix the dry ingredients evenly, then add clean water and turn to mix evenly until the moisture content is appropriate.

(8) 33% soybean stalk powder, 33% cottonseed hulls, 32% sawdust, 1% calcium carbonate, 1% sugar. Dissolve the sugar in a small amount of water and mix it with the dry ingredients, then add clean water and turn to mix evenly until the moisture content is appropriate.

In the above 8 formulas, add 0.1-0.2% carbendazim and 0.1% dichlorvos when mixing the substrate to kill some competing microorganisms and pests. Especially when spawning at higher temperatures, adding appropriate amounts of fungicide and insecticide to the substrate makes the yield increase more obvious.

Spawning

There are many spawning methods for oyster mushrooms, including mixed spawning, hole spawning, layer spawning, and surface-cover spawning. The following mainly introduces layer spawning. Lay a plastic film on the bed surface, spread a layer of substrate about 5 cm thick on the plastic film, then sprinkle a layer of spawn, then spread another layer of substrate, then sprinkle another layer of spawn on top, and finally level and compact it. The bed surface should be flat and shaped like a turtle's back.

Generally, about 20 kg of material is used per square meter of bed surface, with a thickness of 10-15 cm. Before spawning, first take the spawn out of the bottle or plastic bag, put it into a clean basin, break the spawn into pieces the size of jujubes with clean hands, and then spawn it into the substrate. After spawning, cover the surface of the substrate with another layer of plastic film, which helps retain moisture and also prevents contamination by competing microorganisms. As for spawning time, generally it can be done from late August to late April of the following year. However, spring spawning should be early and autumn spawning should be late; a temperature below 15°C is the suitable period for oyster mushroom cultivation.

Management

(1) Management during the mycelial growth phase: The management of the mycelial growth and development stage mainly involves temperature regulation, moisture retention, and prevention of contamination by competing microorganisms. To prevent contamination, the room temperature should be kept below 15°C within 10 days after spawning. Two days after spawning, the spawn begins to germinate and gradually grow outward. At this time, check the temperature changes in the substrate several times a day, and be careful to keep the substrate temperature below 30°C. If the substrate temperature is too high, lift the film and ventilate to cool it down, then cover the film again after the temperature drops. Once the substrate temperature is stable, there is no need to lift the film. After 10 days, the mycelium covers the substrate surface and grows into the substrate layer; at this time, the room temperature can be raised to 20-25°C. If contamination by competing microorganisms is found, sprinkle lime powder on the contaminated area, or wipe it with 0.3% carbendazim. During this period, keep the relative air humidity at about 65%. Under normal conditions, 20-30 days after spawning, the mycelium will have covered the entire substrate. 

(2) Management during the fruiting phase: After the mycelium has covered the substrate, open the doors, windows, and plastic film of the mushroom house for 1 hour each day when the temperature is lowest, then cover them again. This can increase the temperature difference on the substrate surface and promote the formation of fruiting bodies. Water should also be sprayed according to humidity to adjust the indoor relative air humidity to above 80%. When the physiologically mature mycelium encounters suitable temperature, humidity, air, and light, it twists together into many grayish-white, millet-grain-sized primordium clusters. At this time, spray into the air to keep the indoor relative air humidity at about 85%, and do not spray water directly onto the substrate surface, so as not to affect the development of the primordia and cause the young mushrooms to die. At the same time, prop up the plastic film, which both ventilates and retains moisture, and the indoor temperature can be kept at 15-18°C. After the primordium clusters form, they grow rapidly. In 2-3 days, the stipes elongate, and when grayish-black or brown flat-round original caps form at the top, a small amount of water can be sprayed onto the substrate surface to keep the indoor relative air humidity at about 90%. Keep the temperature at about 15°C.

Top Dressing

During the peak fruiting period and the late fruiting period of edible mushrooms, the nutrients in the substrate are nearly exhausted. Applying fertilizer in time during this period can significantly increase the yield of edible mushrooms and improve their quality.

Manure soil fertilizer: Crush sun-dried pig and cattle manure, pre-wet it with the clear liquid from lime water, and pile it for fermentation for 15 days; add 50% fertile mud and a small amount of plant ash, mix well, and when edible mushroom yield drops sharply or dead mushrooms appear, clean the bed surface, remove old roots, and spread the manure soil fertilizer on the bed surface.

Straw liquid 

Use decomposed, sun-dried straw, add 100 times water, boil to obtain the liquid, and after cooling, spray it to make edible mushrooms grow robustly.

Cottonseed liquid: Add 10 times water to cottonseeds, boil to make a liquid, and after cooling, add 3 times clean water before use.

Food liquids

Take 10 kg of non-moldy soybeans (4660,-12.00,-0.26%), wash them clean, soak them, add 50-60 kg of water, boil, filter off the broth, add water to 200 kg, and spray; take 10 kg of carrots, chop them, add 15 kg of water, boil for 30 minutes, filter to obtain the juice, add 3 times water to make a 25% carrot juice for spraying; add 1 kg of solid glucose to 100 kg of water, and after it dissolves, a 1% glucose solution is obtained, which can be sprayed directly.

Mushroom root soup

Take 5-10 kg of mushroom roots, wash them clean, add 10-15 kg of water, boil for 15 minutes, take the clear liquid, add 50 kg of water, stir well, and spray it; this can promote the growth of mushroom primordia.

Harvesting