By Vina Medenilla
There are thousands of mushroom species worldwide, but not all of them are edible. “One indicator that mushrooms are poisonous is that it has white gills,” said Emma Tolentino, farmer, ATI learning site cooperator, and owner of Eco Natural Integrated Farm, during an AgriTalk webinar on mushroom production.
Tolentino, also known as the mushroom queen of Tarlac, mainly cultivates paddy straw mushroom or straw mushroom (Volvariella volvacea), one of the common types of edible mushrooms that thrives in warm temperatures. “For paddy straw mushrooms or volva, its gills are greyish pink. If this is the case, more or less, it’s edible,” said the mushroom grower.
It is also called “kabuteng saging” or “kabuteng dayami” because the substrates used in growing this involve banana leaves and dayami or rice straw. It has a shorter growing period of two weeks or less compared to other varieties like oyster mushroom that need to be grown for a month. Straw mushroom is also homothallic or self-fertilizing, which means it can sexually reproduce without mating. Since paddy straw mushrooms are grown through banana leaves, these are high in potassium. They also contain high lysine that helps human body tissues grow and recover from damage.
Unlike plants, mushrooms are not grown in seeds, but through spores. Mushroom cultivation is an eco-friendly way to reduce agricultural waste, while growing them for profit or consumption provide health and monetary benefits.
Paddy straw mushrooms can thrive indoors and outdoors as long as the temperature of 35 to 38 degrees celsius is attained. These must be grown in high areas that can’t be reached by water and in places without direct sun and farm animals.
You won’t really need a large space or expensive materials in constructing the bed where your straw mushrooms will grow, the vital thing in the process, aside from the materials, is cleanliness.
Cultivating paddy straw mushrooms
The materials you will need to start cultivating paddy straw mushrooms are:
- dried banana leaves for the mushroom bed
- paddy straw mushroom spawn from a hygienic and reputable source
- kakawate (Gliricidia sepium) leaves
- bamboo and wire for a structure to elevate the bed from the ground
- transparent plastic sheets to cover the spore bags once placed on the bed
- a spray solution made of rice wash and brown sugar.
Making the bed. The growing bed is composed of layers of banana leaves planted with spawn where mushrooms develop. There are cases that this is elevated by a constructed bamboo flooring to prevent termites and ants from going into the bed, but Tolentino also prefers placing the growing bed directly on the ground, especially if there’s no presence of pests in the area. Bamboo is also attached on both ends of the bed that will keep the plastic sheets in place later on.
To make the growing bed, collect dried banana leaves that are still attached to the tree and not the leaves that have fallen on the ground to elude from getting any bacteria that may not be beneficial to your mushrooms. Bind together banana leaves at least four inches wide using string. The leaves must be bound properly so the leaves won’t fall off during the process. Once tied, cut them into pieces with a length of 12 to 14 inches per bundle.
Submerge the banana leaf bundles in clean water overnight. To prevent it from floating, put wood, or any clean and heavy material on top of the bundles to keep them submerged. This will allow all parts of banana leaves to absorb water equally. The next day, remove the water and make sure to keep the moisture of banana leaves at 40 to 50%. Its color must be chocolate brown. If it’s too wet, let it sit for a while to release the excess water.
An alternative to banana leaves is rice straw. There are cases that they are mixed in the bunches as well. In terms of the ratio, there’s no specific amount of banana leaves, but as long as you have a larger amount of banana leaves than the rice straw, then you can mix them altogether. Since rice straw is acidic, it could infect the banana leaves, hence, a smaller amount can minimize the risk of this happening. You can also opt to use pure rice straw without banana leaves or vice versa. The process of preparing rice straw is the same with the banana leaves: group them into bundles, soak in water overnight, and lay it on the ground or on an elevated growing space.
Setting the growing bed in an outdoor setting. To prevent any termites from occurring, you may elevate the bed using bamboo. The bed can go up to three meters high depending on the number of layers of prepared banana leaves that you plant to stack on top of each other.
As per Tolentino, five to six layers of banana leaf bundles are recommended during summer, while for the rainy season, eight to ten are recommended because the more layers there are, the more heat the growing space can accumulate.
Planting the spawn. Before doing this step, remember to sanitize your hands with alcohol, or even prior to preparing the banana leaves. After setting up the bed, plant the spawn one inch away from the edges of the bed. The reason for planting them on the sides is for the mushrooms to grow even after more layers of banana leaves are added on top. Putting the spawn in the middle won’t allow the mushrooms to grow.
The spawn is usually accompanied by tobacco midribs, sawdust, and dried leaves of ipil-ipil plant (Leucaena leucocephala). Tolentino says that you also can add rice straw, banana leaves, or anything that is high in nitrogen. The paddy straw spawn can also be bought in agricultural stores or through mushroom farmers. Tolentino sells straw mushroom spawn for P80 per 500 mgs.
Adding kakawate leaves. Next is to put the kakawate leaves on the bed, which will help keep insects away and will keep the bed warm, especially during the rainy season. Kakawate leaves have a high nitrogen content that will also serve as the food for the mushrooms. Acacia leaves can also be used as an alternative.
Spraying the bed with a solution. Instead of synthetic fertilizers, make a natural fertilizer using one liter of rice wash and two tablespoons of brown sugar, molasses, or muscovado. Spray this mixture every time you add a layer of banana leaf bundles to feed the mushrooms with nitrogen. After this, repeat the whole procedure until you have created the five layers of banana leaves.
Incubation. Tie the wires to the bamboo poles found on both ends of the bed then hang the plastic sheets into it. This will help the plastic not to be carried by strong winds.
Since paddy straw mushrooms thrive better in hot climates, plastic sheets will help in controlling the temperature for the beds, especially if you are growing them outdoors. Make sure that the plastic and wire will not touch the bed as it might hinder the growth of the mushrooms. Clear, transparent plastic sheets are preferred because it will allow you to check the mushrooms without having to remove the cover, helping to maintain the temperature inside.
Let the bed sit for five days after being planted. On the fifth day, open it for five to ten minutes and cover it again with plastic. But this time, the plastic must have a wider distance from the bed to let air circulate inside. This allows carbon dioxide to be released from the bed, allowing the mushroom pinheads to grow more.
Harvesting. After 10 to 14 days of incubation, mushrooms will be visible and ready for harvest. Simply twist the mushrooms and pull it all out. Make sure that nothing has been left in the ground.
See the actual demonstration here:
If you live in a cold humid area like in Baguio, Tolentino says that it is still possible to cultivate straw mushrooms indoors. The temperature of 35 to 38 degree celsius must be maintained or else, there will be no formation of mushrooms. If this is the case, it is better to grow them during the summer season as this is a warm-loving mushroom.
In Tolentino’s farm, they do not remove the plastic cover on each mushroom bed to control the temperature inside that is crucial for the growth of mushrooms. Tolentino added that removing the cover is feasible if the grower has the capacity to control the temperature of the mushroom house.
In cultivating any type of mushroom, the most important thing is to maintain a clean environment. Take a bath before starting the process and regular use of alcohol to disinfect one’s hands is also recommended. If possible, use a lab gown, surgical gloves, and a facemask to avoid contamination of bacteria.
Insights shared by Emma Tolentino during the first day of Agritalk 2020: Urban Agriculture Promotion Webinar Series about Mushroom Production held last August 19, 2020.
For more information, visit the Agritalk 2020: Urban Agriculture Promotion Webinar Series Facebook group.
Screenshots from the video demonstration of mushroom production posted by ATI Central Luzon.