Enoki mushrooms (Flammulina velutipes) are a gourmet fungi recognized for their delicate flavor and distinct texture. Cultivated Enoki develop the signature long, thin, white stems and small caps seen in grocery stores, unlike their shorter, brownish wild counterparts. Growing Enoki at home requires a structured process that mimics the fungi’s natural growth cycle and uses specific environmental controls to achieve this desired appearance. This guide details the stages for successfully growing these mushrooms indoors.
Preparation and Substrate Selection
A successful Enoki harvest starts with selecting the proper growth medium. Hardwood sawdust is the ideal substrate, providing the lignin and cellulose the Flammulina velutipes mycelium consumes. Sawdust is often supplemented with nutrient-rich materials like rice bran to accelerate colonization and increase yield.
After mixing and hydrating the substrate to 60–65% moisture content, it must be sterilized to eliminate competing organisms. Sterilization is achieved by heating the substrate above 250°F (121°C) for at least 90 minutes, typically in a pressure cooker. Once cooled, the sterilized substrate is inoculated with Enoki spawn (such as grain spawn or liquid culture) and transferred into glass jars or specialized grow bags.
The Incubation Phase
The incubation phase, or “spawn run,” is when the mycelium colonizes the entire substrate block. This stage requires a warm, dark environment to encourage rapid growth of the fungal network. Ideal temperatures range between 64°F and 77°F (18°C and 25°C), and containers must be kept in complete darkness.
The mycelium spreads outward, consuming nutrients and binding the loose substrate into a solid block. Relative humidity inside the container should range from 75% to 85% to support growth. Colonization is complete when the entire substrate appears uniformly white, a process that takes between two and four weeks.
Inducing the Fruiting Body
Transitioning the colonized block to fruiting requires a sudden environmental shift. This is initiated by a temperature shock, moving the block to a significantly colder environment. The temperature must drop by 15 to 20 degrees Fahrenheit, ideally settling between 50°F and 61°F (10°C to 16°C) to stimulate the formation of mushroom “pins.”
The long, slender stems of cultivated Enoki result from managing carbon dioxide (CO2) and light. High CO2 levels prevent caps from expanding, forcing the stems (stipes) to stretch vertically in search of fresh air. This is achieved by partially restricting air exchange around the block, often by placing a collar around the container opening to trap the CO2 produced by the mycelium.
The mushrooms need exposure to very low or indirect light, which encourages the white coloration. Once tiny primordia, or pins, form, the CO2 restriction must be slightly eased to allow gradual fresh air exchange. This air increase, combined with a consistently high relative humidity of 85% to 95%, allows the stems to elongate without drying out. Maintaining this balance of low temperature, high CO2, and high humidity produces the characteristic long, thin clusters.
Harvesting and Storage
Enoki mushrooms are ready for harvest when stems reach the desired length and caps remain small, typically when the cluster is three to four inches tall. Harvest the entire cluster at once by cutting the stems cleanly at the base, directly above the substrate block, using a sharp knife or scissors. This prevents damage to the underlying mycelium, which is necessary for potential subsequent harvests (flushes).
To maximize freshness, store the mushrooms in a way that manages moisture content. The preferred method is to place the uncut cluster into a paper bag or a breathable, perforated container. Storing them in the refrigerator, ideally outside the high-humidity crisper drawer, will keep them fresh for up to a week.