How to Grow Enoki Mushrooms at Home: Blocks, Kits, Fridge

The enoki sold in supermarkets, with their bundles of long white stems and tiny caps, look nothing like the wild mushroom they come from. Wild Flammulina, known in Britain as velvet shank, has broad orange caps and short stems that turn dark and velvety with age. Much of the difference comes from how cultivated enoki are grown, especially the cool temperatures and the build-up of carbon dioxide (CO₂) around the clusters.

That makes enoki a rewarding species to grow at home, because you can steer the result. Give the clusters plenty of fresh air and you get stubbier mushrooms with bigger caps. Restrict it and you move toward the long, thin bundles you see in the shops. This guide covers sawdust blocks, ready-made kits and a surprising method developed for teaching that uses an ordinary household refrigerator.

Enoki at a glance

Factor	What sources report
Substrate	Hardwood sawdust with bran. One study used 80% sawdust and 20% rice bran. A Japanese teaching method used spruce sawdust with rice bran
Spawn run	18°C in darkness for 25 days (Lee et al. 2025). 25°C in a small-bottle teaching method (Togashi and Fukuchi 2022)
Fruiting temperature	7 to 18°C (North Spore). 14 to 16°C (Lee et al. 2025). 5 to 10°C in a fridge (Togashi and Fukuchi 2022). 17 to 21°C for one golden enoki kit (Root Lab)
Humidity	98 to 100% while pinning, then 88 to 95% (North Spore)
CO₂	500 to 1,000 ppm while pinning, under 1,000 ppm as the mushrooms grow, for cap-forming yields (North Spore)
Light	About 300 lux for 8 hours a day in one study (Lee et al. 2025). 100 to 200 lux for one kit (Root Lab)

The fruiting temperatures vary widely between sources. That reflects different strains: commercial white enoki strains, golden strains sold to home growers, and lab strains don’t all behave the same way. Follow your spawn supplier’s figure first and use the others as a guide. North Spore lists its golden enoki as Flammulina filiformis, the name now often used for the cultivated East Asian enoki, and also as F. velutipes. If you want more background on the mushroom itself, see our enoki guide.

How CO₂ shapes enoki

A 2025 study in the Journal of Fungi by Lee and colleagues grew enoki on 80% sawdust and 20% rice bran. The bags were colonised in darkness at 18°C for 25 days and then fruited at 14 to 16°C and 80% humidity. During fruiting, the researchers compared two CO₂ levels:

At 1,000 ppm, the caps averaged 10.23 mm across.
At 10,000 ppm, they averaged only 4.82 mm, less than half the size.

High CO₂ also increased the number of fruit bodies. The authors traced the smaller caps to reduced activity of genes involved in cell division in the cap. Their results on stem length are mixed: one section found no significant difference, while others describe longer stems at high CO₂. The practical point is clear, though. Stale air gives you many small caps. The authors also warn that CO₂ building up in poorly ventilated bottles or bags causes uneven quality.

North Spore gives the home-grower’s version of the same lesson. High CO₂ lowers yields and causes long, stringy stems with small caps, so it recommends keeping CO₂ under about 1,000 ppm.

You want	Fresh air	Result
Shop-style enoki	Restricted, for example by keeping a sleeve of bag around the cluster	Long, thin stems and tiny caps
Rustic, golden enoki	Plenty of fresh air once pins form	Shorter stems, larger caps and, according to North Spore, better yields

Method 1: Sawdust blocks

Step 1: Make and sterilise the substrate

Mix hardwood sawdust with bran. The Lee study used 80% sawdust and 20% rice bran, and wheat bran is a common alternative. Wet the mix so it holds together without dripping, then pack it into filter-patch bags or heat-proof jars. Supplemented sawdust needs full sterilisation in a pressure cooker or autoclave, not pasteurisation. Our article on sterilisation versus pasteurisation explains why.

Step 2: Inoculate and colonise

Add grain spawn once the substrate has cooled. North Spore says a 6 lb bag of its golden enoki grain spawn will inoculate 120 to 165 lb of sterilised sawdust. Keep the bags in darkness while they colonise. The Lee study used 18°C for 25 days, and the Japanese teaching method used 25°C. A cool room is fine.

Step 3: Trigger fruiting with cold

Enoki is a cold-weather mushroom. In the wild, Wild Food UK records velvet shank fruiting from December to April. Once the block is fully colonised, move it somewhere cooler and very humid. North Spore’s range is 7 to 18°C, with 98 to 100% humidity while pins form. Open the bag above the substrate, or cut an X in it as Root Lab suggests for its kits, and mist the opening daily. Our guide to cold shocking covers this kind of temperature drop in more detail.

Step 4: Decide on the shape

For long, thin stems, leave most of the bag standing above the substrate as a sleeve once pins form, or roll a paper or plastic collar around the cluster. This keeps CO₂ and humidity high around the stems. For more natural-looking clusters, cut the bag back and give the mushrooms gentle fresh air. Root Lab recommends reduced fresh-air exchange until pins form, then gentle airflow.

Step 5: Harvest

Cut or pull the whole bundle off at the base. Root Lab suggests harvesting as the caps begin to flatten, to avoid heavy spore drop. For shop-style enoki, harvest earlier, while the caps are still small and rounded.

Method 2: The refrigerator method

A 2022 paper by Togashi and Fukuchi, from the National Institute of Technology, Asahikawa College in Japan, set out to create a simple enoki-growing manual for public science classes. Their key findings:

They used small 200 ml culture bottles.
Spruce sawdust mixed with rice bran produced more fruit bodies than a lab agar medium.
After the spawn run at 25°C, removing the spawn cover and adding water encouraged fruiting.
Fruiting took place in a household refrigerator at 5 to 10°C, and exposure to light encouraged it.

For a home grower, this is a neat trick. Once a jar is colonised, a spare shelf in a fridge (or a cold cellar or garage in winter) can provide the cold that enoki needs. Use a dedicated fridge, or keep the jars sealed apart from food. A colonised jar is still a living fungal culture, and you don’t want spores or moulds near your groceries.

Dense cluster of wild velvet shank mushrooms with broad orange-brown caps among ivy — Wild velvet shank has broad orange caps and short dark stems, very unlike supermarket enoki. Photo: John Haddon via iNaturalist, CC0 1.0.

Method 3: Kits and outdoor options

If you’d rather skip sterilisation, golden enoki kits are widely available. Root Lab’s kit instructions give a fruiting range of 17 to 21°C and warn that warmer conditions can shorten the stems or make the pins abort. They also recommend humidity of 90 to 95% or more and light of about 100 to 200 lux. That is warmer than most other sources suggest, which shows again how much strains differ. Always follow the instructions that come with your kit.

Outdoors, North Spore says golden enoki may fruit in spring or autumn in cooler regions, in beds or containers made from straw or wood chips mixed with grain spawn. It notes that indoor growing is this species’ strength. Grain spawn should not be used to inoculate logs.

Food safety: always cook enoki

Enoki has been linked to Listeria outbreaks. The US Centers for Disease Control and Prevention (CDC) says a 2020 outbreak was the first known one linked to enoki. It also investigated a 2022 outbreak in which five people in four states were hospitalised. CDC’s advice is to cook enoki thoroughly. It also says that pregnant women, adults aged 65 and older, and people with weakened immune systems should not eat raw enoki at all. North Spore likewise advises cooking its enoki thoroughly, and suggests eating only a small amount the first time you try it, in case of an allergic reaction.

Home-grown enoki deserves the same care. Keep your growing area clean, refrigerate the harvest, and cook it before eating.

Do not forage “wild enoki” casually

Wild Food UK treats velvet shank as an edible species that should be cooked, but it has a dangerous look-alike. The site warns that the funeral bell (Galerina marginata) is “similar and deadly poisonous”, and can be told apart partly by the ring (skirt) on its stem. It also points to spore print colour: velvet shank’s is off-white, while some look-alikes, such as the common rustgill, have rust-coloured spores. These details matter, but a description or photo is never enough on its own. If you want to try wild Flammulina, learn it in person from an experienced local forager first. If something unexpected appears among your enoki blocks or beds, don’t eat it.

Quick troubleshooting

Thin, stringy stems and very small caps when you didn’t want them: too much CO₂. Open up the bag and add gentle fresh air.
Short stems and pins that stall: probably too warm for your strain. Move the block somewhere cooler.
Pins drying at the tips: humidity is too low. Raise it to the high 90s and avoid air blowing directly onto the cluster.
Nothing happening after colonisation: enoki needs a real chill. Try a cooler spot, or the fridge method above.

For a side-by-side look at the temperatures different species prefer, see our temperature cheat sheet.

Sources and further reading

Featured image: wild Flammulina by A Hill via iNaturalist (CC0 1.0). Inline photo by John Haddon via iNaturalist (CC0 1.0).

How to Grow Enoki Mushrooms at Home: Blocks, Kits, and the Fridge Method

Enoki at a glance

How CO₂ shapes enoki