Velvet shank mushrooms, information about cultivation technology
Velvet shank (Flammulina velutipes) is a mushroom fungus that grows on deciduous stems in hill and lowland stands.
It is grown for the pleasant flavour it imparts to culinary dishes. In many countries, it is cultivated in an intensive industrial system, Japan holding the supremacy with 80% of world production and Taiwan with 10%.
In Japan, the velvet shank has been known for a long time, and in Europe, it appeared only after 1925. More in-depth studies on cultural technology were made after 1965.
Botanical particularities
The shape of the cap is globular, then convex and flat at maturity. The color of the cuticle is yellow at the edge, towards the center brown-orange, darkening with age, becoming brown with orange shades. At first, the gills are white, then they turn brown-yellow as they age. The stem is 5-17 cm long, with a thickness of 0.3-0.5 cm, which narrows towards the top as the stem elongates.
Ecological requirements
The carpophore develops at a temperature of 15-16ºC. The size of the cap depends on the CO2 concentration which must be less than 0.06%.
Cultivation
It is similar to other mushroom species and is especially accessible to private growers.
The growing medium is horse manure with the addition of wheat straw (12-15%). The substrate is laid in flat layers, placed 16-18 cm thick, or in polythene bags (diameter 50 cm and height 30-35 cm).
For incubation, the temperature is 20ºC, and for fruiting 10-20ºC.
The harvest period is 40-45 days from the appearance of the first mushrooms. The yield obtained amounts to 18-27% of the weight of the nutrient substrate.