Harvesting your own mushrooms is a great way to ensure that they’re always fresh, and you can save money in the process. You can grow your own mushroom easily. For this, you will need mushroom spores. You can collect mushrooms using mushroom spore prints. Even though you collect mushroom spores, Do mushroom spores go bad? I have the perfect answer for you. Let’s find out more about it.

Do Mushroom Spores Go Bad

Do mushroom spores go bad?

They sometimes go bad when not appropriately preserved. When storing mushroom spores, you need to ensure they are not exposed to direct sunlight or heat. If spores go bad, they will not germinate. Let’s talk more about mushroom spores, how to preserve them, how they go bad, and how to identify expired mushroom spores.

What are mushroom spores?

Mushroom spores are fine powder-like substances that can be seen with a microscope. These spores come from mushrooms and fungi. Spores are produced in the fruit body of mushrooms and are ejected when ripe or even sometimes before the mushroom reaches maturity. Spores are released for reproduction purposes of the mushroom.

When the mushroom is ready, it “gives birth” (also called casting or spring ), releasing its spores into the air.

These spores can be transported long distances by air. Some mushrooms like puffballs release their spores when the mushroom is disturbed. Spores are microscopic and can only be seen with a microscope. There are thousands of spores in a single mushroom. Spores’ color ranges from white to black but can also be translucent or yellowish.

What is the average shelf life of mushroom spores?

The shelf-life of most mushroom spores is about two-three years. Mushroom spores that are ‘activated’ (germinated) can live longer, even for decades. Some mushroom spores can even live for more than a century. For example, the spores of some fungi have been found to be 250 years old.

Can mushroom spores go bad?

Yes, mushroom spores can go bad. Spores can lose their viability or germination capacity if not stored properly. When spores are not properly preserved, they can lose viability or germinate capacity. Spores that go bad will not be able to reproduce and grow mushrooms.

Over time, some mushroom spores will die on their own. The life cycle of a mushroom spore will run its course.

When storing mushroom spores, keeping them in a dry and dark environment is essential. It’s no good for the spores to be exposed to direct sunlight or heat. You should not keep mushroom spores in the refrigerator unless the conditions are just right. (which we will discuss later)

Why preserve mushroom spores?

Some mushrooms can be difficult to cultivate or may take a long time. In some cases, mushroom spores need special equipment and preparations to grow. Preserving the spores of these mushrooms can ensure that you have a supply on hand to help with cultivation.

Further, some mushrooms are ready only once every few years. So if you have a lot of people who want your mushrooms, preserving their spores can ensure that they have a steady supply. The spores of rare edible mushrooms are commercially valuable since they can be harvested all year round by storing spores.

Do Mushroom Spores Go Bad

How to store mushroom spores?

There are two ways you can store mushroom spores for future use.

  1. Make spore prints
  2. Make spore syringe

The former method is the easiest and has most of the advantages. But it is possible to store mushroom spores in a spore syringe too.

How to make spore prints?

First, you need to find a mushroom whose spores you want to collect. Pick a mature mushroom that has grown all the way and is about to release its spores. Cut off the stem of the mature mushroom just above the surface where it meets the ground to make a “cutting.”

Place this cutting gills-side up on a piece of paper and cover with a container.

Check periodically, and when the spores start to drop, you will see them as a cloud of fine dust on the paper. These are the mushroom spores you will use for your spore print. When ready, gently lift the paper and allow the spores to drop onto a clean, dry surface. 5-6 hours later, you will notice that most of the spores have settled below the paper. Cover this with glass to keep humidity away and put it somewhere dark. After a few days, you will have a spore print. This is the mushroom spore print used to make a spore syringe.

You can directly preserve this spore print or create a spore syringe out of spores collected this way. You can use either a spore print or a spore syringe to grow mushrooms.

If you want to keep the spores this way, you will have to fold the spore print in tin foil or a piece of paper and store it in a zip lock bag. This way, spores will not contact outside weather and be preserved for long. The spore print is the best way to store mushroom spores since they are ready and can be used immediately.

Further, spore prints can last for decades, and they won’t need a refrigerator. However, the spore print must remain in an airtight container as the hydration can cause the spores to go bad. They can remain resilient at any room temperature as long as they stay good and dry.

How to make a spore syringe?

The second way is to store mushroom spores in a spore syringe. In this case, the spore syringe is prepared from the spores collected from the mushroom. You can use a glass jar and a syringe to prepare the spore syringe. First, sterilize the jar and the syringe. Then put some sterile water in it and add a few drops of bleach to avoid contamination.

Put the mushroom spore print over the jar and scrape the spores into the jar with a sterile scalpel.

Now, fill the spore with mixed water into the syringe. You may have to fill and remove the water about two to three times until the spores get mixed well. Once you are sure that spores have distributed well in the water, fill the syringe for the last time and close the cap. Keep this syringe in a dark room or in an incubator for 2 to 3 days. This step will ensure that the spores get hydrated well.

After about 2 to 3 days, you can store the syringe in a refrigerator. Spore syringes can be ready within a few days, and you can use them immediately to create mushroom grow kits. A spore syringe is a method that requires more effort and time to prepare, but it can be stored for a very long time if kept in a refrigerator.

How to store mushroom spores in a refrigerator?

If you want to keep the spore syringe for a very long time, you have to store it in a refrigerator. You can simply keep the syringe in a clean refrigerator without putting it in any container. Make sure to check for mold or any other contamination every two-three months.

Mold can cause a dangerous infection, so it is important to keep your spores safe until you are ready to use them.

If you find mold or any other contamination, discard the spore syringe and make a new one. At any point, if you want to use your spore syringe, open it and add sterilized water to your spore syringe.

Add about ten drops of bleach to the solution and close the spore syringe with the cap tightly. Shake well and allow it to sit for a few hours to kill bacteria in the solution. After a few hours, the contents of the spore syringe will be clean, and you can use it to grow mushrooms. In the end, it is essential to store your spores in a clean place and check for contamination regularly. If you do this, you can keep the spore syringe for decades.

Do Mushroom Spores Go Bad

How do I know if my spore syringe is bad?

There are distinct differences between a good spore syringe and a bad spore syringe. Spore syringes usually go bad when they get contaminated. Contaminated spore syringes are not transparent and have a gelatinous look, while good spore syringes have a clear transparent brownish color. If your spore syringe is bad, you have to throw them away immediately because they are not only unusable for growing mushrooms, but they can cause dangerous infections as well.

How long can spore syringes last unrefrigerated?

If prepared with sterile equipment, spore syringes can last unrefrigerated for about six months or so. If some germs and mold grow in the solution, it can become unusable and cause dangerous infections. Fortunately, you can tell if the spore syringe is contaminated by looking at the syringe. Contaminated syringes are not transparent and have a gelatinous look. You should not use these types of spore syringes.

How long do mushroom spores last refrigerated?

It is difficult to tell how long mushroom spores can last in the refrigerator because many factors determine the shelf life of the spores. One factor is the spore concentration in the solution. Another major determinant of the shelf life of spores is temperature and humidity conditions, especially room temperature and moisture.

Spores also lose some of their viability over time, which gradually becomes less effective.

A spore syringe can easily last for about 2 to 3 years if kept in a refrigerator. On the other hand, if your spore syringe is not properly prepared and stored, it can lose its effectiveness even before it expires. A spore syringe can last for decades if prepared right, kept in a cool dark place, and appropriately stored in a refrigerator.

Can mushroom spores survive in a freezer?

The spores of mushrooms are very resistant to high temperatures as well as low temperatures. However, they can not tolerate high heat and freezing conditions for long. So, when stored in a freezer, there is a high chance of spores becoming non-viable. Freezing does not kill spores immediately. They become ineffective as time passes and exposure to high or low temperatures increases. Therefore, it is vital to use the spore syringe stored in a freezer within the first three months of making it and use it as soon as possible.

How long do mushroom spore prints last?

Mushroom spore prints can last for about 18 years if dried and stored properly. However, making a spore syringe out of the spore print is even better because it will be ready for use in just a few weeks.

How long do mushroom spores stay viable?

Mushroom spores stay viable for about ten to 18 years if properly stored. If the spores are not prepared with sterile equipment, they will likely lose their effectiveness before the expiration date.

Can you store mushroom spore prints in the fridge?

Although you can store mushroom spore prints in a fridge, it is not recommended as they can get contaminated if the container is not sterile and closed properly. For the mushroom spore prints to last longer, they must be kept in a clean, airtight container. Otherwise, the spores may lose their effectiveness before the expiration date.

Do Mushroom Spores Go Bad 4

What is the best way to store mushroom spores?

The best way to store mushroom spore prints for extended periods of time is to store them in a dark, dry, and cold place. However, spores should be used as soon as possible because they lose their effectiveness over time. If you have to store spore prints for a longer time, fold them on a piece of filter paper and keep them in an airtight container. Add a few drops of sterile water to the spore print before closing the container. This way, it will stay wet and fresh for longer.


Mushroom spore prints can last for decades if prepared right, kept in a cool dark place, and stored properly in a refrigerator. However, the spore prints do not necessarily have a shelf life or a specific expiration date. Instead, they gradually lose their viability over time, which makes the spores less effective.

Therefore, it is essential to use the spore print stored in a refrigerator within a few months of making it and use it as soon as possible. A mushroom spore syringe can last for about 2 to 3 years if kept in a refrigerator. On the other hand, if not properly prepared and stored, the spore syringe can lose its effectiveness even before it expires. When mushroom spores go bad, the syringe becomes yellowish and gelatinous. This is the first sign that the spores are not viable anymore, and you should get rid of that syringe immediately to stop spreading the contamination to other spore syringes.

Credit to : Miss Mina


Hello, I'm Dr. Chamika. I am a Researcher in Environment and Water quality, Aquatic organisms, and Environmental chemistry. My mission is to help other. You can use this knowledge to enhance your life THE BEST environments you possibly can.

Write A Comment