Key Points for Winter and Spring Management and Stimulation Techniques of Shiitake Mushrooms

Winter and spring management of shiitake mushrooms is the management of the fruiting period, which determines the level of economic benefit.

The fruiting period is a transitional stage from mycelial development to fruiting body development. When management shifts from the spawn-running room to the fruiting period, the mycelium must reach physiological maturity. The standards for maturity are: first, a slight trembling sensation when holding the mushroom bag in the hand; second, the amount of wart-like growths accounts for 3/4 of the bag surface area and they become soft and elastic; third, pigment secretion covers 2/3-1/2 of the bag surface; fourth, the cultivation time must be 60-70 days, with an effective accumulated temperature of 1200°C.

Before moving out of the shed, the fruiting shed should first be built. A two-shed system can be adopted: one for cultivating small mushrooms and the other for cultivating flower shiitake. The fruiting shed should be built in a location with flat terrain, convenient drainage and irrigation, high and dry with good sun exposure, and close to clean water sources. Sheds should be built together to facilitate the management of loading and unloading materials. Specifications of the fruiting shed: 3.2-3.4 m wide, 20 m long, and 2.2-2.4 m high per shed. It can hold 2000 bags.

The most suitable temperature for the development of small mushrooms is around 15°C. They grow longitudinally and transversely at the same time, and the mushroom body is well-proportioned. The suitable humidity is 85%, and the light should mainly be scattered light.

Management requirements during the fruiting period: ventilate in the morning during early winter and early spring; ventilate from 12 noon to 4 pm during deep winter. When temperatures are high, the ventilation time should be longer; when temperatures are low, it should be shorter. Fresh air and humidity should be maintained inside the shed, and a straw curtain should be placed over the small mushroom shed.

Flower shiitake is a type of malformed mushroom produced during the shiitake production process when conditions unsuitable for its growth are provided. The mechanism is that the surface of the cap grows more slowly due to stimulation from dry and low-temperature conditions, while the interior of the cap grows faster, causing the cap skin to crack and expose the white mushroom flesh, thus forming flower shiitake.

Different flower shiitake are produced at different stages of young mushrooms. When the cap diameter reaches 2-2.5 cm, chrysanthemum-petal-shaped flower shiitake are produced. This type of flower shiitake has the best quality and the highest price. When the cap diameter reaches 4-5 cm, scattered flower shiitake of poorer quality are formed.

The optimal temperature for cultivating flower shiitake is 8-18°C, and a relatively large temperature difference is needed. The humidity in the early stage should be 65%-70%, and 55%-65% in the later stage is more suitable. Cultivating flower shiitake requires relatively strong light and relatively high humidity; otherwise, nail mushrooms that are wet inside and dry outside will form.

The standard for moving mushroom bags from the small mushroom shed to the flower shiitake shed is when the young mushroom cap diameter is 2-2.5 cm. In winter, clear days with a light breeze are the best weather for cultivating flower shiitake. In early winter and early spring, the film can be lifted in the evening and morning to cool the mushrooms. In deep winter, it is advisable to lift the film from 10 am to 4 pm. Cover the film at night.