Troubleshooting Common Mushroom Growing Problems (2024)

Ah, mushrooms! Those fascinating, mysterious organisms that spring forth from the earth, conjuring up images of whimsical fairy tales and woodland enchantment. As a grower, you’ve most likely reveled in the excitement of watching your mycelium spread, anticipating the miraculous moment when those first primordia emerge. Yet, if you are reading this article, you know it is not without its challenges and setbacks. This article is devoted to troubleshooting some common issues that arrise when growing mushrooms at home.

Table of Contents:

1. Contamination
2. Slow Growth
3. Small or Malformed Mushrooms
4. No Mushrooms / Not Pinning
5. Over Pinning / Many Pins, But Only a Few Mushrooms Grow
6. Optimal conditions for growing P. Cubensis Reference Chart
   • Inoculation
   • Colonization
   • Fruiting

Contamination:

Contamination is a common problem encountered in mushroom cultivation that can have a variety of potential causes. Contamination occurs when other microorganisms like bacteria or mold grow in the substrate, competing with the mycelium and hindering mushroom growth.

There are several potential causes of contamination, including:

• Poor sterilization techniques: If the substrate or equipment is not properly sterilized, it can introduce competing microorganisms that cause contamination.
• Inadequate airflow: If there is not enough airflow in the growing area, it can create an environment that is conducive to contamination.
• Cross-contamination: If tools or equipment are not properly sterilized before use, they can introduce contaminants to the substrate.

To identify and correct contamination issues in your mushroom grow, there are several foundational practices and advanced techniques that can be used:

• Proper sterilization practices: Ensure that all equipment and substrate is properly sterilized before use to prevent contamination. This may involve using a pressure cooker, autoclave, or other sterilization methods.
• Proper air flow: Ensure that there is adequate air flow in the growing area to prevent stagnant air and reduce the risk of contamination.
• Environmental monitoring: Dialing in your environment is paramount to reduce contamination. Make sure to monitor the temperature, humidity, and fresh air flow in the growing area to ensure that they are within the appropriate range for mushroom cultivation.
• Early detection: Monitor the substrate and mycelium closely for signs of contamination, including discoloration, strange odors, or unusual growth patterns.
• Agar testing: Agar testing involves taking a small sample of the substrate or mycelium and culturing it on agar to identify any contaminants. While perhaps overkill, agar testing can be a useful tool for identifying the source of contamination and taking corrective action.
• PCR testing: PCR testing involves using genetic testing to identify the specific type of contaminant in the substrate or mycelium. This can be a more advanced technique for identifying and correcting contamination.

By implementing these practices, you can identify and correct contamination issues in your mushroom cultivation and promote healthy and productive mushroom growth.

Slow growth:

If your mycelium is growing slowly or not at all, it may be due to insufficient temperature or humidity levels. Check the environmental conditions in your growing area and adjust them as necessary.

Slow growth in P. Cubensis mushrooms can be caused by a variety of factors, including:

1. Incorrect environmental conditions: P. Cubensis mushrooms require specific environmental conditions to grow at an optimal rate. If the temperature, humidity, light, or air flow is not within the appropriate range, the mushrooms may grow slowly or not at all.
2. Contamination: Contamination in the substrate can inhibit mycelial growth and cause the mushrooms to grow slowly or not at all. It’s important to maintain a clean and sterile growing environment to prevent contamination.
3. Inadequate substrate: If the substrate does not provide enough nutrients or moisture, the mushrooms may grow slowly. Consider supplementing the substrate with additional nutrients or adjusting the moisture levels as needed.
4. Genetic factors: Some strains of P. Cubensis mushrooms are naturally slower-growing than others due to genetic factors. If you are using a strain that is known for growing slowly, it may require more precise environmental conditions or additional nutrients.
5. Improper sterilization: If the substrate or equipment is not properly sterilized, it can introduce competing microorganisms that inhibit mycelial growth and slow down the growth of the mushrooms.

If you are experiencing slow growth in your mushroom cultivation, it’s important to evaluate the environmental conditions and take corrective action as necessary.

Small or Malformed Mushrooms:

Small or malformed mushrooms are a common issue encountered in mushroom cultivation that can be caused by a variety of factors. These factors include:

• Nutrition: If the substrate does not provide enough nutrients, the mushrooms may grow small or malformed.
• Insufficient light: If the mushrooms are not receiving enough light, they may grow small or misshapen.
• Overcrowding: If there are too many mushrooms growing in a small area, they may not have enough space to develop correctly.
• Environmental factors: Environmental factors like temperature and humidity can also affect the growth of mushrooms. If these factors are not within the appropriate range, the mushrooms may grow small or malformed.

To correct small or malformed mushrooms, there are several actionable practices that you can use:

• Adjust the substrate: If the mushrooms are not receiving enough nutrients, consider adjusting the substrate recipe by adding more nutrients or using a different substrate.
• Increase light: If the mushrooms are not receiving enough light, consider adjusting the lighting conditions in the growing area to provide more light.
• Decrease overcrowding: If the mushrooms are overcrowded, consider removing some of them to provide more space for the remaining mushrooms to grow.
• Adjust environmental factors: If the temperature or humidity is not within the appropriate range, consider adjusting these factors to promote healthy mushroom growth.
• Harvest at the right time: Be sure to allow your mushrooms to fully mature before harvesting, as harvesting too soon can prevent future pins from forming and result in small or malformed mushrooms.

No Mushrooms / Not Pinning:

If your substrate has been fully colonized but no pins are developing may be caused by several factors, including:

1. Environmental factors: If the temperature, humidity, lighting, or air flow in the growing area is not within the appropriate range, pins may not form.
2. Incorrect substrate: If the substrate does not provide the appropriate nutrients, moisture, or pH level, the mushrooms may not form.
3. Genetic factors: Some strains of mushrooms are more difficult to fruit than others, and may require more precise environmental conditions or additional nutrients to form mushrooms.

To correct a lack of pinning, there are several actionable practices that you can use:

1. Adjust the environmental conditions: Ensure that the temperature, humidity, lighting, and air flow in the growing area are within the appropriate range for p. cubensis cultivation during the fruiting phase. The appropriate enviromental conditions during this phase are as follows:
   • Temperature: 70-75°F (21-24°C)
   • Humidity: 90-100%
   • Light: Indirect sunlight or artificial light for 12 hours per day
   • Air flow: Adequate air flow to prevent a buildup of carbon dioxide
2. Adjust the substrate: Ensure that the substrate provides adequate nutrients, moisture, and pH level for mushroom growth. This may involve adjusting the nutrient content, moisture level, or pH level of the substrate.
3. Cold shock: Cold shocking, as mentioned earlier, can be an effective method to induce fruiting in some mushroom species. This involves exposing the mycelium to colder temperatures for a period of time to trigger a stress response that stimulates the formation of fruiting bodies.
4. Light deprivation: Some mushroom species, such as P. Cubensis, can be induced to fruit by depriving them of light for a period of time. This involves covering the growing area with a dark cloth or other material to create a dark environment for the mycelium.
5. Spore print: In some cases, a lack of pinning may be due to poor spore quality or an old culture. If this is the case, obtaining a fresh spore print from a reliable source and using it to inoculate new substrate may help to induce fruiting.

Over Pinning / Many Pins, But Only a Few Mushrooms Grow

Advanced troubleshooting steps for the issue of many pins but only a few mushrooms maturing:

1. Pinning density: Pinning density may be a factor in why only a few mushrooms are maturing. Ensure that your substrate is not overcrowded with pins and that there is enough space for the mushrooms to grow.
2. Nutrient availability: Ensure that your substrate has enough nutrients for all the pins to mature into mushrooms. This may involve using a different substrate or supplementing your substrate with additional nutrients.
3. Light and humidity: Ensure that your mushrooms are receiving adequate light and humidity. Insufficient light or humidity can cause pins to form but not mature into mushrooms.
4. Air flow: Ensure that your mushrooms are receiving adequate air flow. Insufficient air flow can cause a buildup of carbon dioxide, which can hinder the growth of mushrooms.

Advanced troubleshooting steps for the issue of not pinning:

1. Temperature: Ensure that your substrate is being maintained at the appropriate temperature range for pinning. For P. Cubensis mushrooms, this is typically between 70-75°F (21-24°C).
2. Humidity: Ensure that your substrate is being maintained at the appropriate humidity levels for pinning. For P. Cubensis mushrooms, this is typically between 90-100%.
3. Light: Ensure that your substrate is receiving adequate light for pinning. Indirect sunlight or artificial light can be used to provide the mushrooms with light.
4. Fruiting conditions: Ensure that your substrate is being exposed to the appropriate environmental conditions for fruiting, including lighting, temperature, humidity, and air flow.

Optimal conditions for growing P. Cubensis Reference Chart

Here is a comprehensive summary sheet of the optimal conditions for growing P. Cubensis during the various phases of growth:

Inoculation:

• Temperature: 70-80°F (21-27°C)
• Humidity: 90% or higher
• Sterilize substrate and equipment to prevent contamination
• Use a spore syringe or other inoculation method to introduce spores to substrate
• Monitor for signs of spore germination and mycelial growth

Colonization:

• Temperature: 70-75°F (21-24°C)
• Humidity: 90-100%
• Monitor for signs of contamination and take corrective action as needed
• Ensure substrate is fully colonized before proceeding to fruiting phase

Fruiting:

• Temperature: 70-75°F (21-24°C)
• Humidity: 90-100%
• Light: Indirect sunlight or artificial light for 12 hours per day
• Air flow: Adequate air flow to prevent a buildup of carbon dioxide
• Maintain high humidity levels to encourage pinning and fruiting
• Monitor for signs of excessive pinning or failure to pin, and take corrective action as needed
• Allow mushrooms to fully mature before harvesting to promote future pinning

By following these optimal conditions during each phase of growth, you can improve your chances of successfully growing healthy and potent P. Cubensis mushrooms at home. It’s important to carefully monitor the environmental conditions and take corrective action as needed to promote healthy mushroom growth.