Day-to-day Reishi growing diary

Hello, mushroom lovers!

I just want to share my journey of growing amazing medicinal mushrooms — Ganoderma — aka Reishi in Japan, aka Lingzhi in China. Actually, my species is Ganoderma multipileum, also called Antler Reishi because it produces beautiful, deer antler-like mushrooms.

The very first steps for almost ALL mushroom species are the same. We need initial genetics (spores, liquid culture, or mycelium on agar) and sterile grain jars or bags.

You can follow this grow report and use some tips and tricks for growing magic mushrooms; and for other wood loving species like Lion's Mane, Shiitake etc.

Let's get started!

Starting materials and equipment:

• Agar culture (Ganoderma Multipileum)

• Whole unpeeled rice

• Grain bags, polyfill (or cotton), filters, rubber bands

• Hardwood sawdust

• Rice bran (or wheat bran)

• Bulk bags, filters and rubber bands

• Pressure Cooker

• Still Air Box

• Gloves, Face mask, 70% alcohol

Day 1 (Part 1). Grain and Bags preparation.

I prepared whole rice bags. To do this I soaked the grain in water overnight and boiled it for 30 minutes. Drain, let it dry for another 30 minutes. Then, I filled autoclavable bags and made air filters for better steam sterilization and gas exchange during the colonization period.

Day 1 (Part 2). Grain and Bags preparation

This is actually how whole, non-peeled rice in husks looks. Nothing else is added to the grain substrate.

To make these bags, I used an autoclavable bag. For the air filter needed for gas exchange (and better steam sterilization), I used a plastic autoclavable cylinder plug, cotton or polyfill fiber, a protective filter paper-cloth cover, and rubber bands.

I fill the bag with grain (up to 1/3 of the volume) and wear cylinder plug on a bag.

Then I fill the plug with a synthetic fiber like polyfill (or cotton).

After that, cover it with filter cloth (folded twice to create 4 layers) and secure it tightly with a rubber band on top.

For sterilization in a pressure cooker, I cover the filters with aluminum foil to keep them dry.

Day 2. Grain Bags Sterilization

I sterilized the bags in a pressure cooker for 2.5 hours and let them sit until they cooled down to room temperature. The next day, my bags were ready for inoculation. Actually, I inoculated them 3 days later after sterilization, and it's totally fine!

Pro tip: You can use sterilized grain within 3-4 weeks of storage.

Day 5. Inoculation

My inoculation method is an agar sample.

In the photo below, you can see an agar slant with mushroom culture.

I mainly use this method for long-term mycelium storage, as well as for multiplying mycelium through agar-to-agar transfers and further inoculation. By the way, agar slants are the best method for preserving genetics for years. From my experience—at least 3 years for sure!

If you are interested in this technique, check out the detailed guide here: Agar Slants

Since I had to open the bags for agar inoculation, I proceeded in the Still Air Box.

All tools, agar and grain bag inside SAB. I inoculated only one grain bag with Ganoderma Multipileum also called Antler reishi (it produces deer antler-like mushrooms).

After inoculation, I placed the bag in a dark closet and left it to incubate at room temperature. During the colonization period, temperatures fluctuated between 70–77°F (21–25°C).

Day 7. Colonization period and first signs of mycelium

Two days after inoculation, visible signs of mycelium growth can be seen on the top of the rice grain. Unfortunately, it's hard to capture in a photo how the mycelium from the agar sample comes down and spreads onto the grains.

During the colonization period, I don’t do anything extra — just stay patient and wait for the mycelium to spread.

Day 19. Colonization Period Updates

In just two weeks (actually, in 10 days) after inoculation, the grain bag with my Antler Reishi was fully colonized.

Reishi is considered a slow-growing mushroom (especially during the fruiting stage), but colonization was surprisingly fast. The mycelium was very hungry, aggressive, and rapid — it’s one of the fastest genetics I’ve ever grown! For comparison, here’s my bag with Antler Reishi and Lion’s Mane. Both were inoculated two weeks ago, but the difference is incredible!

It’s time to take the next step!

Day 20 (Part 1). Bulk Bags and Spawn Transfers in a Still Air Box

It was a busy day because I wanted to divide this one spawn bag into several different transfers:

1. Grain to Agar (G2A) - need to prepare agar

2. Grain to Grain (G2G) - need to have grain bags

3. Grain to Bulk (Spawn to Bulk - S2B) - need to prepare Bulk bags

So, I prepared three bags with a substrate mix of 95% hardwood sawdust and 5% rice bran. Gypsum is beneficial, but I didn’t add it.

The moisture level is around 60%. I used the traditional "field capacity" test to check:

grab a handful of the substrate, squeeze it as hard as you can, and only a few steady drops should come out—this means the moisture level is perfect!

For these bags, I used large heat-resistant grow bags, filled them with the substrate, and closed them with plastic cylinder plugs with caps. I then pasteurized them for 8 hours. Once they cooled to room temperature, they were ready for the Spawn to Bulk step. Each bag weighs about 3 lbs (1.5 kg).

Day 20 (Part 2). Transfers

I set up a Still Air Box (SAB) and placed all the necessary stuff inside.

Then I made transfers in SAB one by one:

1) Grain Spawn to Agar

I prepared no-pour agar cups (5PP heat-resistant cups) and put grain spawn sample in each cup. This was mainly for demonstration—to show one of the ways to save mycelium.

Pro Tip: You can also inoculate an agar plate with grain spawn samples from a pre-made grow kit. This way, you can save the genetics for future attempts and save money! 😉

2) Grain to Grain Transfer I used the same spawn bag for Grain to Grain transfer, inoculating three more grain bags with Antler Reishi. This method speeds up colonization significantly.

Pro Tip: You can also multiply mycelium from pre-made grow kits using Grain to Grain transfers! Detailed process here: Grain to Grain Guide

At this stage, the mycelium is strong enough, reducing the risk of contamination. Colonization also much faster because you're using active mycelium, and each grain becomes a starting point for mycelial growth. If you introduce just 1 tablespoon of spawn, you’ll create at least 100 active points of mycelium growth!

3) Spawn to Bulk Finally, I did a Spawn to Bulk transfer (moving the spawn to the fruiting substrate) to prepare three blocks for mushroom fruiting.

Pro Tip: One grain spawn bag (about 300 g or 0.7 lbs) is enough to inoculate 20–30 grain or bulk bags. I only needed one tablespoon per bag, but of course I used much more.

The day was all about expanding mycelium and preparing for the main (fruiting) stage. Things are looking great, and I’m excited to see how these blocks develop!

Day 23. Mycelium Run Update

Here are my fruiting blocks 3 days after the Spawn to Bulk transfer.

The grain has turned white again, and the mycelium has already spread onto the sawdust substrate.

It’s time to remove the caps and replace them with breathable filters (4 layers).

Day 29. Mycelium run update

My fruiting blocks with Antler Reishi - 9 days after the Spawn to Bulk transfer.

Cool! ❤️

Day 34. Mycelium run update

Antler Reishi fruiting blocks 14 days since Spawn to Bulk. Mycelium growth has become faster.

Photo with different light.

The other side of the same blocks.

Beautiful mycelium ropes.

Run mycelium!

Day 44. Bulk colonization update

Antler Reishi fruiting blocks — 24 days since Spawn to Bulk!
The mycelium growth is looking pretty good so far!

Here’s a shot from the other side of the bags. One of the bags still has a big gap in colonization, but no worries, that's totally normal at this stage.

Exciting update! The fastest bag has already started forming a fruit body — right through the air filter!
Even though it’s not fully colonized yet, it’s clearly eager to grow.

Starting from today, I have to leave all the bags completely unattended for about 7–10 days while I'm away.
Let’s see what surprises they’ll have for me when I get back! ;)

Day 54. Fruiting bag colonization update

Antler Reishi fruiting blocks — 34 days since Spawn to Bulk.

As you might remember (from previous post), I had to leave all the bags completely unattended while I was away from home. And here’s the update — 10 days later, and wow, what a change!

The blocks have turned rock-solid, like real bricks.
When you touch them, they’re actually warm, which means mycelium really produce heat.
However, the bottom parts are still catching up — they’re not fully colonized yet and are moving a bit slower.

One bag still has a bald area, but the bottom part is almost ready — it just used its energy in a different direction.

And here’s the best surprise! One of the pins grew so much while I was gone — it’s now almost a full-sized fruiting body!

Really looks like an antler.

Even better — another bag formed pins right on the air filter!
Mushrooms always find a way! ;)

So, two bags are already fruiting!

I still need to give them another 3–5 days for the bottoms to fully colonize. Which gives me the perfect window to start setting up the fruiting chamber (grow tent) and get everything ready.
Super excited for the next phase! Stay tuned!

Day 55-60. Grow tent preparation and Fruiting Conditions

First, I assembled my grow tent and placed a metal shelf rack inside.

DIY Ventilation with HEPA

Next, I built a ventilation with a HEPA filter.

Then, I installed it on top of the tent.

This setup filters air through the HEPA filter (installed in white connector) and pulls air in. The incoming air also creates positive pressure inside the tent, which helps to reduce the risk of airborne contaminants.

Pro Tip: This method is much better for mushroom cultivation than setups where air is blown out of the tent, as those often draw in dirty air through gaps in the tent (especially from the floor).

DIY Humidifier

After that, I built a humidifier using affordable items: a plastic food container, a PC fan, a simple fogger, a water float valve, some pipes and connectors and big water bottle (8 Qts/Liters).

The humidifier (a plastic box inside the tent) is connected to a large 8-liter water tank placed outside the grow tent.

Water from the large tank flows down and automatically fills the humidifier to the correct level, regulated by a float valve.

I only need to refill the big tank once a week and it's super convenient!

The fogger creates fine mist. The fan pushes mist through the pipe and helps spread it evenly throughout the tent.

I ran a few tests to make sure everything was working properly, and the grow tent was finally ready for the fruiting stage!

Fruiting Conditions for the next several weeks

• Temperature: it's hot season righ now and temperature in my fruiting chamber fluctuates between 74°–81°F (23–27°C). Sometimes reaching 82°–86°F (28°-30°C) if I turn off the AC.

• Ventilation: 2–4 times per day. I run the system for 15–20 minutes each time. Ganoderma is highly tolerant to CO2, which is a great plus!

• Humidity: 80–85%. I run the humidifier 2–4 times per day together with the ventilation, then let it continue for another 5–10 minutes. Total run time is around 20–30 minutes per cycle.

• Light: 2–4 hours per day (cold white LED).

Note: I’m currently using only a thermometer and hygrometer as sensors. There’s no automation in my setup yet.

Day 60. When pins say go, you go

During the current reishi grow I faced with a dilemma. On one hand, the bags still had uncolonized areas, so I couldn’t remove the air filters and open them up for proper pinning earlier (before they started forming pins on filters). On the other hand, reishi had already started fruiting… yes! through the air filters! That meant I couldn’t wait any longer and had to move them to the fruiting chamber right away.

The pins were literally biting into the filters. Trying to remove filters at this point would completely ruin my early mushrooms. I figured I’d just let things slide. Let them grow through the filters and see what happens.

And just like that, the first day of the fruiting period officially began!

Day 80. Fruiting period update

Reishi are truly slow-growing mushrooms. When cultivation something like Cubensis, Shiitake, Oysters, you can often see changes daily. Sometimes even within a few hours. But with Reishi, it takes weeks to notice a significant difference between pins and proper fruits.

Here we are at:

• Day 80 of the overall grow

• Day 60 since spawning to bulk

• Day 20 since placing the bags in the grow tent

Almost three weeks for the transformation from shapeless pins into these beautiful, antler-like fruits with bright woody texture:

They're beautiful!

Day 90. Reishi fruiting progress

Note: 30 days of fruiting period

The active fruiting phase is the most exciting part of mushroom cultivation. It’s so satisfying to observe every tiny change in growth! 10 days have passed since the last update (see Day 80) and look at them now! Ganoderma have formed more branches and become even more charming.

Reishi don’t look like (typical) mushrooms at all. From some angles, their fruits resemble tree branches or hands from horror movies. Love this feature of reishi. So hilarious!

Day 90. Forced harvesting of the first flush

Note: same day update - 30 days of fruiting period

My reishi still had more growing to do. With time they could’ve developed more branches and size. I would’ve waited a few more days or maybe a couple of weeks. But unfortunately, I had to harvest earlier as I was leaving home. And I didn’t want to leave them unattended for too long.

Bag by bag, I carefully pried up the filter and twisted off all the reishi antlers.

Sadly, this is the end of this grow… almost! ;)