Efficient and High-Yield Techniques for Outdoor Mushroom Cultivation

Cultivating mushrooms outdoors in open ground saves on shelving materials, does not occupy buildings, has low costs, good returns, and is convenient to manage. It is a relatively good planting industry that rural areas should vigorously develop. The cultivation operation techniques are briefly introduced as follows:

1. Material preparation: Generally, the effective area for mushroom cultivation per mu of land is 400 sq m. In advance, prepare 28,000-30,000 kg of fresh, dry, mold-free, pest-free rice and wheat straw, 800-1,000 kg of dry fine cow manure, 8,000-10,000 kg of human and livestock liquid manure, 50 kg of urea, 80 kg of phosphate fertilizer, 120-150 kg of gypsum powder, 50-60 kg of lime, or use 300-350 kg of rapeseed cake to replace the dry cow manure.

The materials for building the arched shed are 200-250 kg of 2 m long bamboo strips, 60-70 kg of plastic film, and 400 straw curtains 2 m long and 1 m wide.

2. Land preparation and bed making: Choose a rice field or other crop rotation field with high, open terrain, smooth drainage, slightly sticky soil, medium fertility, close to a water source, and able to avoid cold wind in winter. In mid-August, plow 16-20 cm deep. After preparing the land, spray the bed surface with 500 times diluted dichlorvos. To kill small animals and harmful insects in the soil, make the beds oriented north-south, 1.2 m wide, with a small soil ridge about 10 cm wide built in the middle of the bed surface, forming two narrow bed surfaces. Also build small soil ridges on both sides of the bed, 15-20 cm wide and 12-15 cm high. The walkway is about 60 cm wide and lower than the bed surface to facilitate drainage. Then arch bamboo strips into a small arched shed, with spacing of about 80 cm, connect the arch tops with horizontal branches, and keep the shed top about 60 cm from the bed surface.

3. Timely composting: Outdoor mushroom cultivation should avoid high-temperature weather, so start composting and fermentation from late July to early August. First soak and wet the various raw materials separately. The rice and wheat straw should absorb enough water, then mix thoroughly. The compost pile is preferably 2.5 m wide, 6-8 m long, and 1.5-1.7 m high. The first layer of material is 30 cm thick, sprinkle a layer of cow manure (or rapeseed cake), pour enough human and livestock liquid manure, then tread firm, and pile the second layer of material on top. The final layer of straw material should be thoroughly watered with liquid manure. Make the top of the pile turtle-back shaped to prevent rainwater from seeping into the pile and affecting fermentation. Generally, turn the pile 4-5 times. The interval before the first turning is about 7 days (turn the pile when the temperature inside the pile rises to 65-70 degrees). The second is 4-5 days, the third is 2-3 days, and the fourth interval is 1-2 days. The total composting period is 20-22 days. Add urea at the first turning, add phosphate fertilizer and gypsum powder at the second turning, and add lime at the third turning. Note that when turning the pile, the straw and manure should be fully mixed and loosened to ensure even fermentation and uniform color of the pile.

4. Filling the bed and sowing: Put the well-fermented compost into the bed while hot, spread it on the bed surface, and let the material temperature slowly drop. Start sowing when the material temperature drops below 28 degrees. Before sowing, level the bed material, pick out manure clumps and debris, with a material thickness of about 15 cm, then evenly sow mushroom spawn on the surface of the material. You can sow in holes, with one hole every 6-8 cm square, or directly broadcast it on the material. Finally, gently pat with a plastic box or wooden board so the spawn contacts the straw material. Use 2 bottles (700 ml) or 1 kg of spawn per sq m. Cover the bed surface with waste newspaper, then cover the arched shed with plastic film and pull it tight with rope to prevent wind from blowing it off, while also covering with straw curtains and other shading materials.

5. Spawn-running management: After sowing, check the temperature inside the arched shed at any time. Generally it must not exceed 28 degrees, and the material temperature should preferably not exceed 30 degrees. Otherwise, ventilate and exchange air in time, cool down, and prevent high temperature from burning the spawn. On windless nights, the film at both ends of the arched shed can be lifted for ventilation to keep the air inside the shed fresh.

Generally, after 7-10 days from sowing, once the spawn has grown into the material, remove the paper covering the surface to let the surface layer of the bed dry slightly, prompting the hyphae to grow deeper into the material. If a small amount of green mold and other contaminating fungi is found, remove it in time and apply lime or spray some fungicide to prevent the contaminating fungi from spreading.

6. Casing soil and watering: When the mushroom hyphae are about to grow to the bottom of the material, apply casing soil. Generally use vegetable garden soil or middle-layer soil from rice fields (preferably sun-dried in advance), or directly use the soil layer in field ditches as the casing material. The soil particles are preferably 1-2 cm in size. It is best to completely cover the straw material. After covering with wet soil, no watering is needed. If dry soil is used for covering, water must be applied after 1 day to increase moisture. Use fine mist and water frequently. After 2-3 days, adjust the moisture of the soil layer so that it feels soft when squeezed by hand but does not stick to the hand. After the soil layer moisture is adjusted, stop watering and cover well with plastic film to let the hyphae develop into the soil layer. After 6-7 days, the hyphae can spread throughout the soil layer. When the hyphae slightly emerge above the soil layer, apply one heavy watering, called "fruiting water." This inhibits the hyphae from emerging above the soil surface, promotes the formation of small fruiting bodies, and enables early mushroom production.

7. Management during the fruiting period: When a large number of pinheads the size of rice grains form between the soil cracks, keep the soil layer moist. When slightly dry, lightly spray some fine mist. On windless nights, open the film on the back side for ventilation. When the daytime temperature exceeds 28 degrees, add straw curtains to cool down, or spray with well water. When the small mushrooms grow to 0.5-1.0 cm in size, increase watering at night. As the mushroom bodies grow, increase the amount of watering. After watering, uncover the film and ventilate for 10-20 minutes. During the fruiting period, always maintain a humid air environment and soil layer, with fresh air, to ensure excellent mushroom quality and also favor high yield.

8. Timely harvesting: Mushrooms must be brought to market in time, otherwise they easily age and open their caps, and quality deteriorates. Generally, from fruiting body formation to harvest takes about 6-7 days. Harvest before the mushroom veil breaks. While harvesting, cut off the mushroom base and put them into plastic bags, or bring them to market with soil attached to maintain freshness. After each flush of mushrooms is harvested, clean the old roots and old spawn blocks on the mushroom bed, stop watering for 1-2 days, and then spray water again to promote the formation of the second and third flushes of mushrooms. When the temperature drops below 4 degrees, stop using water on the bed surface to prevent the soil layer from freezing, and protect the hyphae well so that good mushrooms can continue to be produced in the following spring.