Learning how to grow mushrooms is like any skill. Sometimes you succeed. Sometimes you fail. The important thing is to keep trying and learn from your mistakes.
Still, it can be very disappointing to start what you think will be a successful mushroom project and have it fail. Trust me, I know. It’s happened to me many times!.
Although many factors may influence your success, there are some common mistakes that can be easily avoided. I’ve listed eight big ones below, along with practical solutions.
If you’re just learning to grow mushrooms, review this list to save yourself both time and heartache. Even if you’re a veteran, it never hurts to come back to the basics.
For more information on how to grow mushrooms and troubleshooting I’d highly recommend Paul Stamets’ books:
If you’ve been growing mushrooms at home and your mycelium hasn’t started growing after 2 weeks, don’t panic. This frustrating issue is common for beginner mushroom cultivators. With a few troubleshooting tips, you can get your mushroom culture back on track for healthy mycelial growth.
Why Your Mushrooms Aren’t Colonizing
Mushroom mycelium is the white, thread-like growth that spreads throughout your growing medium before forming mushrooms This is the vital first stage of cultivation If you don’t get vigorous mycelium growth, you won’t get a harvest further down the line.
There are a few key reasons why your mycelium growth may have stalled:
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Contamination Trichoderma mold, bacteria, or another contaminant has taken hold. This competitor organism stopped the mycelium growth in its tracks
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Improper moisture levels: Too much or too little moisture prevents the mycelium from growing optimally.
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Temperature issues: Mycelium grows best within a narrow temperature band. Too hot or cold conditions will slow or stop growth.
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Poor gas exchange: Without enough fresh air exchange, the mycelium can’t get the oxygen it needs.
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Old or weak spores: If using spores, their age or genetics may result in slow growth.
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Nutritional deficiencies: Lack of nutrients in the growing medium stunts the mycelium.
The good news is that all these issues can be fixed! With a few troubleshooting steps, you can diagnose the problem and get your grow back on track.
Step-by-Step Troubleshooting for Slow or No Mycelium Growth
Follow these troubleshooting steps to figure out why your mycelium growth has stalled:
1. Check for signs of contamination.
Carefully examine the inside of your grow bag or jar. Look for unusual colors like green, black, yellow, brown, blue, or red. This indicates mold, bacteria, or another contaminant. Also check for foul, musty odors. Contamination requires you to start over with a fresh culture. Carefully dispose of the contaminated grow to avoid spreading spores.
2. Assess moisture and humidity levels.
Feel the outside of the growing medium. It should feel moist but not soggy wet. Check that tiny droplets of water haven’t pooled on the surface; this encourages contamination. Ideal humidity for mycelium growth is 95-100%. Consider placing your grow bag in a humidification chamber if the air is too dry.
3. Monitor the temperature of the growing area.
Mycelium grows best at temperatures between 75-85°F. Temperatures below 70°F or above 90°F will severely slow growth. Use a thermometer to check the temperature of the room or incubator. Maintain consistent warmth around 80°F.
4. Improve fresh air exchange.
Without enough oxygen, the mycelium suffocates. Open your grow bag in a sterile environment to increase airflow. Or improve ventilation and air circulation in your growing area. Fanning the bags daily also helps.
5. Switch to a liquid culture or mycelium slant.
If using spores, the genetics or age could be the issue. Transferring to a proven liquid culture or mycelium slant can offer faster growth. Order a fresh culture from a reputable vendor online.
6. Add nutritional supplements.
The growing medium may lack key nutrients for optimal mycelium growth. Mix in a supplement like hydrated brown rice flour or a mycological vitamin blend. This gives nutrition a boost.
7. Wait 2 more weeks before discarding.
Sometimes mycelium grows slowly due to variances in genetics and the growing process. Be patient and give it more time before assuming the worst and starting over.
Achieving Faster Mycelium Growth in the Future
Once you get your current grow back on track, make a few adjustments to help your mycelium colonize faster next time:
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Start with a liquid culture or agar slant. The dense mycelium in these cultures leads to rapid growth.
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Use fresh spores. Viability declines over time, so use spores within a year of production.
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Culture on agar first. This strengthens the mycelium before transferring to a grow bag or jar.
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Keep temps in the 75-85°F sweet spot. Maintain steady warmth for fast colonization.
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Gently shake bags daily. This disperses mycelium strands for quicker growth.
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Use moisture absorbent grow mediums like straw or wood chips. This prevents sogginess.
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Improve air flow and humidity. Optimal fresh air exchange and humidity encourages dense, rapid mycelium growth.
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Add nutritional supplements. Hydrated rice flour, wheat bran, coffee grounds, or vitamins give nutrition a useful boost.
When to Start Worrying about Lack of Mycelium Growth
Mushroom mycelium can take 1-4 weeks to show visible growth after inoculation. Wait at least 14 days before troubleshooting. Here are signs that should spark concern:
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No visible mycelium or only tiny pins after 2 weeks
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Weird colors, smells, or textures
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Dried out, crusty growing medium
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Blue or grey mold growing
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Wet, soggy growing medium with pooled water
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Condensation inside the bag or jar
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Temperatures outside the ideal range
If you see these warning signs, take action to diagnose and fix the problem. Catching issues early gives your grow the best chance of success.
Have Patience and Persistence Pays Off
Mushroom cultivation requires diligence and patience. Even experienced growers deal with stalled mycelium from time to time. The key is not to get discouraged. With persistent troubleshooting and modifications, you can get your mushroom culture growing vigorously. Pay close attention and quickly address any signs of issues. Maintain ideal grow room conditions. And don’t give up! With a little time and TLC, your mushrooms will reward you with a bountiful harvest.
Not Enough Air Exchange
Mushrooms don’t need as much fresh air as we do, but they still need it. When you don’t let any air flow through, carbon dioxide builds up, and your mushrooms will grow in as short, spindly things with no caps. Very disappointing.
Solution: Make sure your project has a flow of fresh air. Don’t place things in areas with no air exchange.
If your grow space is sealed, you might want to open it a few times a day to let fresh air in. Just remember that when you let in fresh air, you might also let in contaminants and lower the humidity. It’s a delicate dance!.
Reasons Your Mushrooms Are Not Growing
Let’s look at these reasons in more detail:
6 reasons your mushrooms are not growing
FAQ
What to do if mycelium is not growing?
Why is my mycelium taking so long to grow?
How long until you see mycelium growth?
What stimulates mycelium growth?
Does Mycelium grow in my grow bag after a week?
If you’re not seeing any signs of mycelium growth in your grow bag after a week or two, don’t worry! There’s a technique you can try to kickstart the process. This guide will show you how to cold-shock your grow bag to promote growth and get your mycelium flourishing.
When is molluscum no longer contagious?
Since molluscum contagiosum virus is found only in the upper layer of the skin (epidermis) and does not circulate throughout the body, it cannot be spread by coughing or sneezing. Since the virus is only found in the upper layer of the skin, once the lesions have healed, the virus is no longer present and you cannot transmit it to others.
How long does it take for mycellium to grow?
I usually see mycellium growth in 2 to 3 days. Don’t get worried if you don’t see some for a week though. After a week start getting worried. Optimum temp is 82 to 84 degrees for colonization. Who the hell you callin crazy? You wouldn’t know what crazy was if Charles Manson was eating froot loops on your front porch!
What happens if you let mycelium dry out?
Mycelium, the underground vegetative growth of a fungus, needs a moist environment to thrive and produce mushrooms. Mushrooms themselves are mainly water, so if you let the mycelium dry out or the humidity level get too low then nothing will happen. See the picture to the right?
Does mycelium need a moist environment?
Not Enough Moisture Mycelium, the underground vegetative growth of a fungus, needs a moist environment to thrive and produce mushrooms. Mushrooms themselves are mainly water, so if you let the mycelium dry out or the humidity level get too low then nothing will happen.
Why is standing water bad for mycelium?
Standing water encourages bacterial growth and mold, two things that compete with your mycelium. Although we want to keep our growing media moist, and may even soak it for a day at first, leaving it in standing water is just asking for trouble. Solution: It’s all about drainage.