Mushroom growing in a foil tunnel

Mushroom growing in a foil tunnel

Growing mushrooms in a foil tunnel is a gourmet solution and an idea for a lucrative commercial breeding. Mushroom picking in the forest does not always meet the market’s needs , their quantity and quality depends on whether we were ahead of others pickers. High demand for catering and processing is a big opportunity even for small mushroom growers. A foil tunnel with shading net creates ideal conditions for the development of popular (chanterelles, button mushroom) and fine mushrooms (Shiitake, oyster mushroom). Carefully prepared fertilizer, substrate and good quality mycelium will give you ,with 5 sets and on 1m2 under optimum conditions, up to 20 – 30 kilos of mushrooms yearly.

In this article we will focus on cultivating mushrooms under cover, and in the next one we will introduce growing of other varieties of mushrooms.

Mushrooms in a foil tunnel

Mushroom growing is implemented in foil tunnels, greenhouses, sheds and cellars. To begin the production ,we have to equip the tunnel at the entrance with a separate room for decontamination, sterilization and soil fermentation. Several factors determine the effectiveness of mushroom culture. High humidity in the growing chambers. Difference of temperature between the chambers and the conditions outside, risk of insects and diseases which mainly depends on the size of the crop.

Start of cultivation in the tunnel

In places without air conditioning, mushrooms are grown in two cycles – spring and autumn. First we start with favorable conditions in December (or January) and the second in August. Crops in buildings with air conditioning are grown throughout the year; with such constructions , from 5 to 9 cycles are possible. The use of specialized technology for mushroom cultivation can double or even triple the cultivation cycles.

Type of substrate

Good fertilizer without additives is the best substrate for mushrooms, if animals were fed with oats and hay, fertilizer is an even more valuable nutrient for mycelium. Fresh and with strong smell of ammonia, it is mixed with urea, chicken manure, gypsum and water. Proportions should be adjusted to the mushroom species, strictly adhering to the quantities needed by the variety. Mix the ingredients to get a dark brown substrate PH 7.9 to 8.1 and moisture from 71 to 74%, sterilize before use.

Preparing the substrate when beginning can be problematic. A better and more effective solution is to buy it from the mycelium manufacturers. Appropriately balanced proportions for such matters are beneficial for the development of mushrooms.

Fermentation of substrate

A well prepared substrate is one with a fermentation process completed. After 8 to 12 days depending on the conditions, the fermented substrate is ready to use for mushroom cultivation.

The first step will be to prepare a layer, it is 1 m thick and 4 m wide. If the fertilizer is still dry, we will mix it and irrigate with urea. After 5 – 8 days we add the chicken manure and carefully mix. When everything is ready , we apply a loose layer of fermentation , checking if slurry leaks from below. If nothing happens, then the fertilizer needs to be moistened because it is too dry. But if large puddles appear, add a second layer and mix thoroughly.

From the moment we add the second layer, we check the temperature twice a day. For both measurements, we should get between 63 and 76 ° C. After a few days (from 2 to 4) the temperature drops significantly. Then add the gypsum again and stir, after which the temperature again rises to 74 to 80 ° C. After three days, we add a third fermentation layer and 2 days later, we process the whole mix. We check humidity by squeezing a handful of fertilizer, if a large drop is visible, the substrate is ready and does not require humidification. If we still do not get the described effect, we add water. After another 2 or 3 days, stir if necessary moisturize and apply the last and fourth fermentation layer. Two days later, we sterilize the substrate.

Sterilization of the substrate

Sterilization is carried out to eradicate disease and parasites that can damage mushroom crops. The treatment is carried out 12 days before the first planting and the fermentation time is 12 days.

The fertilizer is transferred to a tunnel or greenhouse, placed on clean shelves in layers of 30 cm. We put a thermometer on it to keep track of the temperature (0 to 100). We check that on all shelves, the fertilizer has the same temperature, if so we can start the sterilization. The whole process is to maintain constant air temperature without significant fluctuations. For 10 hours, we maintain the air temperature between 55 and 60 ° C, and for the next 7 days from 48 to 53 ° C to make the substrate mature.

On the surface of the substrate, a blue-gray mushroom with flecks should appear – this organism is beneficial for mushrooms. We can cool the material to 30 ° C to achieve even better results. The PH parameters of our soil should be between 7 and 7.5 and the humidity should be between 65 and 69%.

Planting mycelium

Mycelium is cultivated on wheat, millet ; the material is stirred with a large part of the mix into the ground, whipping and watering. We spray daily with formalin water, control temperature (optimum 25 ° C) and humidity (90 to 95%). After 14 days, we should see mushroom growth.

Laying out ground cover

When the mycelium grows, we mix low and high peat mixed with chalk. PH soil should continue to be between 7 and 7.5. Disinfection is performed by spraying the substrate with formalin solution and keeping the temperature constant. Regardless of how the cover is prepared, the substrate must be 25 to 27 ° C.

Later care

Moisturizing the top layer is repeated after 5 days, and after 8 days. Mushrooms should emerge from up to 3 cm from the surface. We cover the layer to initiate the development of fruiting bodies. For mushrooms to grow properly, we avoid thermal shock, we bring the temperature to 18 ° C and air up to 16 ° C. We maintain the same humidity level of 90 to 93%. When the fruiting body is the size of matches, the humidity decreases to 85%. Mushrooms within a week should reach a size allowing sale. Every day, we add water as 1 liter/ kg. The ideal temperature for fruiting growth is 18 to 20 ° C and the difference with air is 2 ° C. We also take care of proper circulation of air in mushroom house.


Picking mushrooms requires a lot of precision and accuracy. Cutting too short will waste a few grams, and this makes a big difference at the end. The largest yield is from the first batch that appears after 25 days and lasts for up to 5 days. The next crop comes after a weekly interval . At the end of growing, the substrate is depleted. It can be used as a valuable natural fertilizer for plant breeding.

Mushroom substrate

The used mushroom substrate is a good fertilizer. A valuable source of organic matter and has high macro and micro values. Before using it, it is necessary to examine the soil, remove pests, weed seeds and pathogenic fungi. Heat treatment eliminates all unnecessary ingredients and components then the fertilizer is ideal for next-generation mushrooms, lawns and vegetable crops.

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