How to store Mushroom Spawn for a long time and postpone Spawn to Bulk

How long can Grain Spawn be stored? How to store Mushroom Spawn properly?

Mushroom Spawn storage

Let's figure out real case and real questions from member of Shroomok Growers Community in Discord

Hi Shroomok, please help!
Let me describe the situation.
Spawn jars and spawn bags are fully colonised with healthy mushroom mycelium, everything is okay, I'm happy with results. But I need to keep them and postpone further mycological manipulations (casing or spawn to bulk) for a week or maybe two

❓Can Mushroom Spawn Jars and Spawn Bags be stored at room temperature (about 27°C or 80°F) in the dark place for 1-2 weeks?
❓Is it better to store spawn in the refrigerator or even in fridge till it's time for Spawn to Bulk and Casing?
❓How long can Grain Spawn be stored?
❓How can I "reanimate" mushroom mycelium for further steps and fruiting period?
Thank you 🙏🏻

☝️Answer from Shroomok

How to store mushroom spawn in refrigerator?

Spawn Jars or Spawn Bags with healthy mycelium can be stored in the refrigerator at +2°...+12°C (or 36-54°F). Optimal temperatures are +5°...+8°C (or 41-46°F).

Is it safe to freeze mushroom spawn?

Not recommended! It is believed too low temperatures lower than 0°C or 32 °F can destroy mycelium cells or even kill mycelium.

Actually, we know a real case when mycelium stored in -40°C or -40°F and its viability was fully retained. Actually, there is no advantage for exposing mycelium to such risks.

How long can I store mushroom spawn?

Shroomok can admit from own experience that you can store colonised grain spawn in the refrigerator for 1–2 months and everything will be fine for sure!

Storing in refrigerator is a kind of prolonged cold shocking. In such way you can slow down the mycelium growth.

This option allows you to plan your growing process and postpone further manipulations if your life circumstances require it. Or if you plan Grain to Grain Transfer (G2G), so that you can easily share a single colonised quart spawn jar for about 5-10 jars via G2G transfer

🔴 Recommended guide: Grain to Grain Transfer (G2G)

There are examples of longer storage of grain spawn from our subscribers — 3-4 months and even longer. As a result fruiting and harvesting were successful. There were admitted a slightly slowed down processes of top layer colonisation. Start of fruiting was delayed for a few days.

Use the mushroom spawn within 2-4 months for the best results

How can I reanimate mushroom mycelium before spawn to bulk?

Before Spawn to Bulk and/or Casing small mushroom cakes just leave spawn jars/bags for 1–2 days at room temperature to get mycelium some time to wake up. Then continue your further cultivation manipulations.