Detailed Explanation of Key Points for Water Management in Enoki Mushroom Cultivation

The scientific name of the enoki mushroom is Flammulina velutipes, also known as velvet shank, winter mushroom, and enokitake, among other names; in English it is called “Enoki Mushroom”, and its botanical name is Flammulina velutiper (Fr.) Sing. Because its stipe is slender and resembles golden needle vegetables, it is called enoki mushroom; it belongs to the order Agaricales, family Tricholomataceae, genus Flammulina, and is a type of fungus, algae, or lichen. Enoki mushroom has very high medicinal and dietary therapeutic value.

Morphological characteristics of the enoki mushroom

The enoki mushroom is composed of two major parts: vegetative organs (mycelium) and reproductive organs (fruiting bodies).

(1) The mycelium is formed by germinating spores. Under artificial culture conditions, the mycelium is usually white and fluffy, with septa and branches; when many hyphae gather together, they form the mycelium. Unlike other edible fungi, when the mycelium grows to a certain stage it forms a large number of single-celled oidia (also called conidia), which under suitable conditions can germinate into monokaryotic or dikaryotic mycelium. Some people have found in experiments that the amount of oidia at the mycelial stage of enoki mushroom is related to the quality of the enoki mushroom; strains with many oidia are all of poor quality, and the base of the stipe is darker in color.

(2) The main function of the fruiting body is to produce spores and reproduce offspring. The fruiting body of the enoki mushroom consists of three parts: the cap, the gills, and the stipe; most grow in clusters, and the flesh is soft and elastic. The cap is spherical or flatly hemispherical, 1.5-7 cm in diameter; when young it is spherical, gradually flattening, and when overmature the margin becomes wrinkled and curls upward. The surface of the cap has a thin gelatinous layer, sticky when wet, yellow-white to yellow-brown in color; the flesh is white, thick in the center and thin at the margin; the gills are white or ivory-colored, relatively sparse, of varying lengths, and free or adnexed to the stipe. The stipe is central, hollow and cylindrical, slightly curved, 3.5-15 cm long and 0.3-1.5 cm in diameter; the base of the stipe is connected, the upper part is fleshy (some books say the stipe is fibrous or gelatinous), and the lower part is leathery; the surface is densely covered with dark brown short down. Basidiospores are borne on the hymenium of the gills; the spores are cylindrical and colorless.

Key points for water management in enoki mushroom cultivation

Enoki mushroom cultivation and management have relatively high requirements, especially the water requirements for fruiting body development. Here we introduce the “five-character” water management method for reference. First, maintain moisture. After the mycelium has grown to the bottom of the bag, immediately open the bag and scratch the surface, rake away the old mycelial skin, and cover with wet newspaper or plastic film to preserve moisture and induce budding. For those covered with newspaper, spray water in small amounts several times, 3-4 times a day, to keep the newspaper moist; for those covered with plastic film, water can be sprayed on the ground and into the air to maintain air humidity at about 90%. During this period, open the windows once a day for ventilation, and keep the room temperature at 10-14 °C; after 5-7 days, mushroom buds will emerge in large numbers. Second, reduce moisture. When the mushroom buds grow to 1-2 cm, they enter the growth inhibition stage. At this time, reduce or stop spraying water and lower the humidity. For 3-5 consecutive days, open doors and windows at night to let cold air in to lower the temperature and disperse moisture, bringing the room temperature below 8 °C (4-5 °C is best) and the humidity to about 75%, so that the fruiting bodies are inhibited and grow uniformly and robustly. Third, promote growth. When the fruiting bodies grow to 3-4 cm and enter the elongation stage, spray water 4-5 times a day. The amount of water sprayed increases as the mushrooms grow; keep the air humidity at about 90% (that is, fine water droplets adhere to the bag wall at the base of the fruiting bodies, which is suitable) to promote rapid growth of the fruiting bodies. At the same time, ventilate appropriately, and adopt alternating wet and dry conditions to inhibit cap enlargement and promote stipe elongation. At this stage, the amount of water sprayed should be determined according to the weather: spray more on sunny days and less on rainy days, to prevent root rot and brown spot disease caused by excessive water use, and to prevent excessive water content in the mushroom bodies from lowering quality. Absolutely avoid spraying water onto the caps; if newspaper is found to be damaged, replace it promptly, and if there is standing water on the newspaper, pour it off immediately, to prevent the mushroom bodies from contacting water droplets and producing black spots that affect the commercial appearance. Fourth, supplement. After the first flush of mushrooms is harvested from the fungus bags, the water content drops by 20-30%, and after the second flush is harvested it drops by 30-50%. Therefore, after the first and second flushes are harvested, immediately spray water into the fungus bags after scratching to supplement moisture. The method is: for 2-3 consecutive days, spray water directly into the bags 2-3 times a day, each time just enough to moisten the surface of the fungus column, but do not allow water to accumulate in the bags. To increase yield, a small amount of urea, white sugar, potassium dihydrogen phosphate, etc. can be added to the water to supplement nutrients. Fifth, soak. After the third flush is harvested, the water content of the fungus column has dropped below 50%; at this time the plastic bag can be removed, and the fungus column placed in a pool of water to soak. When the fungus column has absorbed water and recovered to its original weight when the bag was opened, take it out, let it dry slightly, and put it into a bag. Water can also be injected directly into the bag for soaking; after the fungus column has absorbed enough water, pour out the excess water in the bag. After replenishing water, rearrange the fungus bags on the bed frame, cover with wet newspaper, and manage as usual; in this way, two more flushes of mushrooms can be harvested.