What shiitake needs
Shiitake (Lentinula edodes) is traditionally grown on hardwood logs, which can take a long time to start producing. A ready-to-fruit block skips that wait. It likes it cool and humid, with a cooler, wetter start to wake the block up, then slightly warmer conditions as the mushrooms grow.
| Stage | Temperature | Humidity | CO₂ |
|---|---|---|---|
| Pinning | 10–15°C | 90–100% | Not critical |
| Fruiting | 10–21°C (best 15–17°C) | 75–95% | 500–1000 ppm |
Pinning is the start: the block pushes out its first tiny mushrooms, called pins. Fruiting follows, as those pins grow into full caps. Shiitake also tolerates a wider humidity range while fruiting than most gourmet mushrooms.
From a ready-to-fruit block, shiitake takes about 7–10 days to reach harvest.
Why shiitake comes out of its packaging
Every other Flush Block fruits through a small cut in its bag. That directs the block's energy into one cluster. Shiitake is different. It likes to grow all over the block, so it should be removed from its packaging entirely: the box and the bag.
A bare shiitake block often has a brown, slightly leathery skin. That is normal for shiitake, not a sign that anything is wrong.
How to grow shiitake in Flush
- Sterilise your blade. Wipe a clean knife or pair of scissors with alcohol, such as isopropyl alcohol or an alcohol wipe, and let it dry. A clean blade stops you carrying mould spores onto the block.
- Unpack the block. Take the block out of its box. Carefully cut the bag open and peel it away completely, taking care not to dig into the block itself.
- Load it. Stand the bare block inside the cabinet and close the door.
- Choose the preset. In Basic mode, choose the Shiitake preset. Flush holds 16°C, 85% humidity and 750 ppm CO₂ for the whole grow.
- Top up the water. Keep the reservoir filled with clean drinking water. A full reservoir lasts at least a week, and Flush tells you on screen when it is running low.
- Harvest. Expect your first shiitake in about 7–10 days. See below for when to pick.
Want to steer it yourself? In Advanced mode, start in the cooler pinning range, 10–15°C at 90–100% humidity, until you see pins, then move up into the fruiting range of 10–21°C (best 15–17°C). That mimics the cool snap shiitake responds to in the wild.
New to Flush? The set-up guide walks through your first grow, and the Shiitake Flush Block page lists the same conditions.
How to grow shiitake without a cabinet
You can grow a shiitake block without Flush. It is a little less forgiving than oyster mushrooms, because a bare block loses moisture from every side. Outside a controlled environment you are managing humidity and fresh air yourself, and results vary a lot with the room and the season.
- Unpack it the same way. Sterilise a knife or scissors with alcohol, let it dry, and cut the bag away completely.
- Stand it on a plate or tray. A clean plate catches drips and makes the block easy to move.
- Pick a cool spot. Somewhere out of direct sun and away from heaters and air-conditioning vents, within shiitake's fruiting range of 10–21°C. In much of Australia that makes it a cooler-months grow.
- Keep it humid. Mist the block and the air around it several times a day. A loose, clear plastic cover with a few holes, such as a large upturned bag, holds the moisture in. Lift it at least once a day for fresh air.
- Wake it up if it is slow. Shiitake can be slow to pin. A cold shock helps, such as a night somewhere cooler, as can a soak in cold, clean water or a few gentle knocks on the block.
Weighing up a tent or chamber instead? See Mushroom grow tent vs fruiting chamber vs Flush.
When and how to harvest shiitake
Pick shiitake when the caps have opened but their edges still curl slightly under. If you wait until the caps are completely flat, or the edges start to turn up, they are past their best and the texture softens.
Because shiitake fruits all over the block, the mushrooms rarely mature at exactly the same time. Pick each one as it is ready. Hold it at the base and twist it off, or cut it with a clean knife, close to the block.
Most blocks fruit more than once. The first flush is usually the largest, with smaller ones after it. Between flushes, a shiitake block usually needs a rest and then a soak in cold, clean water to rehydrate it before it fruits again. The block is finished when it stops producing.
Cooking shiitake
Shiitake has deep umami flavour and a satisfyingly meaty bite. Its stems are tough, so cut them off and save them for stock. Slice the caps and fry them in a hot pan with oil until browned, then add garlic, spring onion and a splash of soy sauce.
- Broths and noodle soups. Simmer the caps, and the saved stems, in stock for a rich, savoury base.
- Rice dishes and stir-fries. Fried rice, congee and stir-fried greens all take shiitake well.
- Sautés. Cook them whole or halved in butter, then finish with thyme and salt.
- Drying. Spread sliced caps on a tray and dry them in a dehydrator or a very low oven. Dried shiitake keeps for months and its flavour deepens.
Cook shiitake through rather than eating it raw. A small number of people react to raw or undercooked shiitake. Fresh shiitake keeps for several days in a paper bag in the fridge.
Common questions
How long does shiitake take to grow?
About 7–10 days from a ready-to-fruit block, according to the time printed on each Flush Block. Shiitake grown on logs takes far longer, because the mycelium has to grow through the wood first.
Why do you take a shiitake block out of its bag?
Shiitake likes to grow all over the block, so it should be removed from its packaging entirely. Every other Flush Block fruits through a small cut in the bag.
What temperature does shiitake need to grow?
It pins at 10–15°C and fruits at 10–21°C, best at 15–17°C. Flush's Shiitake preset holds 16°C.
Is shiitake hard to grow at home?
From a ready-to-fruit block it is very achievable, but it is less forgiving than oyster mushrooms without a cabinet. A bare block loses moisture from every side, so it needs regular misting and a cool room.
Can I grow shiitake without a Flush cabinet?
You can, but it is harder. Outside a controlled environment you are managing humidity and fresh air yourself, and results vary a lot with the room and the season.
Can you eat shiitake stems?
They are too tough and woody to enjoy as they are. Cut them off and simmer them in stock or broth for flavour, then strain them out.