How To Store Mushroom Plugs

You can store mushroom plugs in a cool, dry place for up to six months if you prepare them properly before long-term storage.

But let me tell you, getting the storage conditions right makes all the difference in whether your mushroom plugs stay viable or turn into a sad, moldy mess.

Whether you’ve just bought a batch of inoculated dowels for your logs or you’re planning to preserve your own homemade plugs, knowing how to store mushroom plugs correctly will save you money and frustration.

In this post, we’re going to cover the exact steps for storing mushroom plugs, why temperature and humidity matter so much, and the common mistakes that ruin your precious spawn.

Let’s dig in.

What You Need To Know About Storing Mushroom Plugs

Storing mushroom plugs really comes down to slowing down the mycelium’s growth without killing it.

When you understand how to store mushroom plugs, you’re essentially putting the mycelium into a state of suspended animation.

The mycelium inside those little wooden dowels is alive and wants to grow.

If you leave them at room temperature, they’ll keep colonizing and eventually dry out or become vulnerable to contamination.

That’s why the golden rule is to keep them cold.

Refrigeration is the most reliable method for storing mushroom plugs for a few months, while freezing can stretch that window even longer.

Here’s what you need to know about the different storage temps.

1. Refrigerate For Short-Term Storage

The best way to store mushroom plugs for up to three months is in your refrigerator.

Just toss the sealed bag or container right into the veggie drawer.

The cold temperature, usually around 35 to 40°F, drastically slows down mycelial activity without killing it.

You want to make sure the plugs are in a breathable bag that’s not completely airtight.

If they’re vacuum-sealed with no airflow, excess CO2 can build up and stress the mycelium.

A paper bag inside a plastic bag with a few small holes works great.

This is how to store mushroom plugs for spring inoculation when you buy them in the fall.

2. Freeze For Long-Term Storage

If you need to store mushroom plugs for six months or longer, freezing is your go-to option.

But freezing requires a bit of caution because thawing can cause condensation that leads to contamination.

For best results, let the plugs thaw slowly in the fridge for 24 hours before using them.

Never thaw them at room temperature as that sudden change can shock the mycelium.

Mushroom plugs stored in the freezer can remain viable for up to a year or more.

Just make sure your freezer stays at a consistent 0°F or below.

The key when storing mushroom plugs in the freezer is to use a sealed container to prevent freezer burn.

3. Keep Them Away From Light

Light isn’t necessarily lethal to mushroom plugs, but it’s best to keep them in the dark.

Direct sunlight can heat up the bag and cause condensation inside.

This moisture creates a perfect breeding ground for green mold and bacteria.

So when you’re storing mushroom plugs, always choose a dark spot in the fridge or freezer.

A cardboard box or an opaque container works perfectly.

Darkness keeps the mycelium dormant and happy.

This is a simple but critical part of how to store mushroom plugs correctly.

4. Check Moisture Levels Twice A Month

One of the biggest mistakes people make when storing mushroom plugs is letting them dry out.

You’d be surprised how quickly wood dowels lose moisture in the fridge.

So you should check your plugs every couple of weeks to make sure they still feel slightly damp.

If they feel dry, you can add a few drops of sterile water to the bag.

But don’t overdo it, as too much water will cause bacterial growth.

The ideal moisture content for storing mushroom plugs is the same as when they were fresh, around 45-55%.

A quick squeeze test will tell you if they’re still good.

If the plugs crumble in your hand, they’re too dry and likely dead.

How To Extend The Shelf Life Of Your Mushroom Plugs

Learning how to store mushroom plugs isn’t just about picking a spot in the fridge.

It’s about the whole process from the moment they arrive at your door.

Proper handling can extend the shelf life far beyond what most people expect.

Consider these tips to get the most out of your spawn.

1. Inspect Them Immediately Upon Arrival

When you get mushroom plugs in the mail, don’t just toss them in the fridge.

Open the package and give them a good sniff and look.

Healthy mushroom plugs have a fresh, earthy smell, like the forest floor.

Any sour or fermented odor means contamination is beginning to take hold.

Also check for any green, black, or orange spots on the dowels.

If you spot any contamination, separate those plugs and don’t use them.

This is the first step in proper storage of mushroom plugs because you never want to store a bad batch.

2. Divide Your Plugs Into Smaller Batches

Storing mushroom plugs in one giant bag is risky.

Every time you open the bag, you introduce warmer air and potential contaminants.

So before you store them, divide your plugs into smaller batches.

You can use ziplock bags with a few holes punched in them.

This way, you only open the small bag when you’re ready to inoculate a log.

The rest of your mushroom plugs stay sealed and undisturbed.

This is a professional trick for how to store mushroom plugs efficiently.

3. Use The Right Kind Of Container

The container you use matters a lot when storing mushroom plugs.

Avoid completely airtight containers as they suffocate the mycelium.

Avoid open containers as they let the plugs dry out way too quickly.

The sweet spot is a container or bag that allows for some gas exchange.

You can use a plastic deli container with the lid slightly loose.

Or simply use a paper bag inside a larger plastic grocery bag.

These options maintain humidity while letting carbon dioxide escape.

Proper airflow is essential for how to store mushroom plugs successfully.

Common Mistakes To Avoid When Storing Mushroom Plugs

Even with the best intentions, people still mess up storing mushroom plugs.

Let’s talk about the most common pitfalls so you can avoid them.

Understanding what not to do is half the battle.

1. Leaving Them At Room Temperature

You might think mushroom plugs are fine sitting on a shelf for a week.

Not true.

At room temperature, the mycelium continues to grow aggressively.

They’ll colonize the bag, sweat, and become overly wet.

This creates the perfect environment for trichoderma and other molds.

If you leave mushroom plugs at room temp for more than a few days, you’re risking the whole batch.

Always refrigerate them within hours of receiving them.

2. Letting Them Freeze And Thaw Repeatedly

If you do decide to freeze your mushroom plugs, don’t keep taking them out.

Repeated freeze-thaw cycles cause ice crystals to form inside the wood cells.

These crystals rupture the mycelial network and kill it slowly.

So once you freeze a batch, keep it frozen until you’re ready to use everything.

This is a crucial point in how to store mushroom plugs for the long haul.

Plan your inoculation projects ahead of time to avoid this issue.

3. Storing Mushroom Plugs In High Humidity Areas

Storing mushroom plugs in the same fridge as fruits and vegetables can be tricky.

Produce releases ethylene gas which can affect the mycelium.

Also, condensation from frequent door opening can introduce unwanted moisture.

Try to store your plugs in the main body of the fridge, not the door.

The door experiences the most temperature fluctuation.

A consistent, stable environment is the secret to successful storage of mushroom plugs.

So, How To Store Mushroom Plugs?

Storing mushroom plugs is really quite straightforward once you know the basics.

You can store mushroom plugs in the fridge for short-term use or the freezer for long-term storage.

Always keep them in a breathable container, away from light, and check moisture levels regularly.

By controlling temperature, humidity, and airflow, you can keep your mycelium healthy and dormant.

So take these steps and your mushroom plugs will be ready when you are.

Happy growing, and may your logs be full of beautiful fungus soon.