Growing Morels – The Complete Guide

Morels, with their honeycombed silhouette and characteristic brown hue, are among the most sought-after mushrooms in the world. Valued by gourmets, they are distinguished by a deep flavor, both woody and slightly nutty, which enhances the most refined dishes.

Their unique texture, both firm and delicate, adds an incomparable dimension to cooking. The rarity of the morel, its short season, and its difficulty to cultivate make it a luxury dish, arousing the desire of mushroom enthusiasts and starred chefs. This mysterious mushroom continues to fascinate both for its taste and the challenges it poses to those who try to cultivate it.

 

 

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1. Introduction to Morel Cultivation

Historical Context: The First Steps towards Morel Cultivation

The cultivation of morels has long been considered the Grail of mycologists due to the many unsuccessful attempts to master their complex life cycle.

It was only from the 1980s that American researchers succeeded in cultivating morels in a controlled environment, marking a turning point in the history of this mushroom. In 1982, a team of scientists from Ohio State University succeeded for the first time in producing morels in the laboratory, paving the way for significant advances in the field.

Subsequently, Chinese researchers made remarkable progress, filing patents for improved cultivation methods that enabled more systematic production. These innovations helped transform morel cultivation from an unpredictable process into an increasingly mastered science, although challenges still remain.

 

The Challenges of Morel Cultivation

The cultivation of morels remains a major challenge due to their specific and capricious requirements. This mushroom needs a controlled environment, with precise temperature and humidity, to thrive.

Morels develop in rich soils, often calcareous, and require a complex interaction with soil microorganisms to fruit. They need a delicate balance of nutrients, moisture, and light, which makes their outdoor cultivation subject to climatic hazards and difficult to reproduce on a large scale.

Moreover, the fruiting process of morels is stimulated by specific environmental factors, such as temperature fluctuations or stress events like drought followed by rain. These requirements make morel cultivation a delicate art that combines science, observation, and constant adjustment of growth conditions.

 

Modern Methods of Morel Cultivation

Modern morel cultivation techniques differ from traditional approaches by a better understanding of pre-fructification conditions and the use of specially formulated substrates.

Today, cultivation in controlled environments allows for the reproduction of the natural conditions necessary for mycelium development, making the crops more predictable. Nutrient-enriched substrates, designed to mimic the natural soils where morels grow, are used to promote healthy mycelium growth.

Optimizing pre-fructification conditions, such as precise adjustment of temperature and humidity, is crucial to encourage morels to fruit. Modern methods also include regulating factors like soil pH and managing microbial interactions, which play a key role in the life cycle of the morel.

 

Ecological Impact and Benefits of Home Cultivation

Growing morels at home has many advantages, both in terms of taste and ecology. By cultivating these rare mushrooms yourself, you reduce the pressure on natural morel populations, which are often victims of overharvesting. This practice contributes to the preservation of biodiversity and helps maintain healthy forest ecosystems.

Moreover, home cultivation offers complete control over growing conditions, allowing the avoidance of pesticides or chemicals that can harm the environment. Morels grown at home are thus more sustainable and environmentally friendly, while also providing the personal satisfaction of producing an exceptional mushroom. Additionally, domestic cultivation of morels allows mushroom enthusiasts to enjoy fresh morels throughout the year, which is rarely possible with wild harvesting.

By combining passion, patience, and modern techniques, home cultivation of morels opens up a world of flavors and discoveries for amateur mycologists and gourmets.

 

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2. The Choice of Mycelium and Substrate

The success of morel cultivation largely depends on the choice of mycelium and the preparation of a suitable substrate.

Saprophytic morels, which feed on decomposing organic matter, are the most suitable for domestic cultivation, unlike symbiotic varieties that require a mycorrhizal relationship with specific host trees.

What variety of morels?

Morchella importuna: Known for its conical black morels, Morchella importuna is a species well suited to domestic cultivation, especially in well-drained soils rich in organic matter.

It ideally grows in substrates enriched with composted wood and prefers moderate exposure to shade. This variety requires special attention to maintain proper humidity and temperature conditions, but it rewards the efforts with generous harvests of morels with a pronounced flavor.

Some morels, such as symbiotic varieties like Morchella esculenta, depend on a mycorrhizal relationship with specific host trees such as ash, elm, or apple trees.

These species are not suited for cultivation in open soil because they require a complex interaction with their partner trees to develop. For this reason, it is better to focus on saprophytic varieties that can be self-nourished from substrates rich in organic matter.

 

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3. Optimal Conditions for Morel Cultivation

The cultivation of morels relies on creating an environment that closely mimics their natural habitat. Morels are sensitive to variations in temperature, humidity, and light, and adhering to these specific conditions is essential to promote their growth and fruiting.

 

Soil Qualities:

• Optimal pH: For morel cultivation, the soil should have a pH between 7 and 8. If necessary, the pH can be adjusted by adding calcium carbonate (CaCO₃), such as chalk. A soil analysis is recommended to determine the exact amount of amendment to add in order to correct the acidity.
• Fungal Properties: Check that the substrate does not contain inhibitory substances such as tannins, which can come from certain tree species (for example, conifers or walnut trees) or plants (such as sage or laurel), as well as wood chips or uncomposted leaves.
• Water Quality: Prefer soft and uncontaminated water for irrigation, ideally from natural sources such as rain or streams, to avoid the addition of unwanted minerals.
• Absence of Chemical Products: Avoid chemical treatments, especially fungicides such as glyphosate, which can disrupt the network of symbiotic microorganisms necessary for the growth of morels.

 

🌡️ Temperature:
Temperature management is one of the most critical aspects in morel cultivation. Cultivation should begin when air temperatures are between 10°C and 20°C, typical conditions of spring or autumn. During the mycelium incubation phase, it is crucial to maintain a stable temperature around 20°C.

Subsequently, a gradual decrease in temperature, ideally down to 5°C, is necessary to stimulate the formation of sclerotia. These compact mycelium structures serve as nutrient reserves and are essential for triggering the fruiting of morels. This temperature drop mimics the natural conditions of late winter or early spring, marking the beginning of the morels' life cycle.

 

💧 Humidity:
Morels require a high level of humidity to develop properly. The soil must be kept constantly moist, but not excessively, as water saturation could lead to the rotting of the mycelium.

A fine irrigation, such as that provided by a misting system or drip irrigation, is recommended. This type of watering helps maintain a constant and controlled humidity without damaging the fragile mycelium. It is important to avoid watering with jets of water that are too strong, as they may disturb the soil and destroy the delicate developing structures.

 

☁️ Light:
Morels are mushrooms that prefer diffuse light, similar to that found in undergrowth or shaded forests. They do not like direct sunlight, which can dry out the substrate and compromise fruiting.

To control light exposure, the use of shade nets, tunnels, or partially covered greenhouses is ideal. These installations allow for the recreation of an environment where the light is filtered, while providing protection against extreme weather conditions, such as wind or heavy rain, which could affect the growth of morels.

 

By combining these parameters with a well-prepared substrate and quality mycelium, you can create a microclimate conducive to morel cultivation, thereby maximizing your chances of successfully growing this delicate and sought-after mushroom.

At the substrate level: Soil preparation is crucial to promote the growth of morels and optimize fruiting.

• pH : The substrate should have a slightly alkaline pH, ideally between 7 and 8, measurable with pH test strips. It may be necessary to amend with calcium carbonate, Meudon white, or limestone lime. Avoid lime rich in magnesium, which is generally not suitable for mushroom cultivation.

• Organic matter: As a secondary decomposer, morel mycelium will appreciate soil rich in already pre-decomposed organic matter. If you have wood chips, the ideal would be to let them compost for a year, then incorporate them into the top 5 centimeters of soil in spring or summer. Manure should also be 2 to 3 years old before being mixed into the soil for morels. A good substrate mimics the natural forest soil of morels, thus promoting their development.

• Humidity and Drainage: The soil must be kept moist, but it is essential to ensure good drainage to avoid water stagnation that could harm the development of morels. Preliminary soil preparation, such as digging to make the soil clumpy and aerated, is necessary to create a favorable environment for the mycelium. It is also recommended to install a drip irrigation system to maintain constant moisture without saturating the substrate.

 

Importance of Organic Matter (OM)

Morels, saprophytic mushrooms, depend on advanced decomposing organic matter for their nutrition. Organic amendments must be well incorporated into the topsoil layer (10 to 15 cm deep) and preferably applied before or during the summer, taking advantage of the heat to accelerate decomposition and neutralize potential contaminants.

 

Recommended Organic Matter Inputs:

• Composted Hardwood Wood Chips: Enrich the soil with well-balanced organic matter.
• Composted Manures: Provide essential nutrients and improve soil structure.
• Digestate from Methanization: Resulting from the anaerobic decomposition of organic matter, it constitutes a rich amendment.
• Vermicompost (Lombricompost): This compost, enriched by the activity of earthworms, supports soil health and stimulates beneficial microorganisms.

To avoid soil saturation, it is recommended to limit inputs to about 1 to 2 kg per square meter per year. Organic matter harbors nitrifying bacteria, such as Pseudomonas putida, which plays a symbiotic role with the mycelium of morels, helping to enrich it with nutrients at the time of sclerotium formation.

 

Soil Preparation and Layout

Soil tillage is a key step in establishing a good growing bed for morels, especially if the plot is newly dedicated to this crop. A well-prepared soil improves growth conditions.

• Weed Reduction: If the plot is still free of any crops, perform several false sowings to reduce weeds before starting the cultivation.
• Amendment and pH Regulation: Amendments to adjust pH or control harmful populations must be incorporated immediately after plowing, before the final soil preparation.
• Soil Structure: The soil must be loose with medium-sized clods (about the size of an egg) and formed into raised beds 0.80 m to 1.50 m wide to facilitate drainage.

 

Irrigation and Moisture Management

Humidity is a crucial factor for morel cultivation, and the irrigation system must be adapted to the soil characteristics to maintain an optimal environment throughout the different stages.

Key Instructions:

• Pre-Sowing Saturation: The soil must be well saturated with water before sowing the mycelium.
• Moisture Maintenance: Keep the substrate constantly moist to promote mycelium growth.
• Irrigation Precautions: Avoid watering the mycelium directly during propagation and refrain from watering young morels measuring less than 3 to 4 cm to prevent damage.

 

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4. Installation of the Culture

Reception and Storage of Mycelium

To ensure the quality of the mycelium, it is important to follow certain steps during its receipt and storage:

• Reception of the mycelium: The mycelium is generally delivered between mid-October and mid-November. 
• Immediate use: If weather conditions are favorable, it is best to use the mycelium upon receipt to maximize its chances of success (see the "Sowing management" section).
• Storage of mycelium: If immediate use is not possible, open the boxes and place each bag on a shelf in a cold room maintained at a temperature of 2°C. If you do not have a shelf, the boxes can be stacked ensuring that the bags do not stick to each other.
• Storage material: Keep the delivery boxes as well as the bubble wrap to protect the mycelium bags outside of cultivation periods.

 

Soil Preparation and Inoculation

The inoculation phase is crucial for successfully cultivating morels. At La Mycosphère, two main techniques are recommended for seeding:

1. Broadcast sowing: Spread between 200 and 300 g of mycelium per square meter, then cover it with 2 to 4 cm of soil. This method is simple and ensures uniform soil coverage.

2. Cluster sowing: Bury 100 to 200 g of mycelium in holes 10 cm deep, spaced 50 cm apart. Although more laborious, this technique protects the mycelium from contaminants and improves its growth by directing the filaments towards the surface.

Before inoculation, it is essential that the soil is well moist, either after natural rain or thanks to a fine watering. To ensure natural shading and maintain good humidity, you can lightly sow cereals such as wheat or rye over the mycelium. This also helps protect the mycelium from the wind.

 

Temperatures for Morel Mushroom Sowing

To start sowing, the temperature under the climate shelter must not exceed 20°C and must remain below this value for a sustained period. This temperature should be measured 10 cm above the ground, at the peak of the day.

 

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5. Maintenance and Monitoring of the Culture

To ensure optimal mycelium growth, regular maintenance is essential. Here are the steps to follow to guarantee the success of your morel cultivation:

Mycelium Monitoring

After inoculating the soil, it is crucial to carefully monitor the appearance of mycelium growth signs. Look for the "flashes", those concentric circles that appear on the soil surface, indicating the expansion of the mycelium. This process can vary in duration, usually from 1 to 3 weeks, depending on environmental conditions such as temperature and humidity.

Watering

Maintaining a constant level of humidity is vital for the growth of mycelium. Ensure that the soil remains moist but avoid excess water that could lead to rotting or stagnation, which are harmful to the cultivation. The use of perforated pipes or a micro-drip system is recommended for gentle watering. Avoid watering young morels directly to prevent disturbing their delicate development.

 

Protection against Parasites

Morel cultivation can be threatened by various parasites, including insects and molds. To minimize these risks, install a shade cloth and a protective tarp. These devices help create a controlled environment, reducing the risk of contamination.

For effective biological control against larvae, slugs, and other pests, you can use Bacillus thuringiensis (BT), a bacterium naturally found in the soil that specifically targets harmful insects without damaging the crop. Be sure to follow the manufacturer's instructions for proper use.

 

Bird and Rodent Management

Birds and rodents can also pose a threat to morel crops by digging in the soil or uprooting young mushrooms. To deter them, you can use protective nets or natural repellents. Installing physical barriers around the cultivation areas can also help protect your harvest.

 

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6. Fruiting: Encouraging the Growth of Morels

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7. Harvesting and Post-Harvest

1. Harvest Period: Morels are mainly harvested in the spring, usually between March and May in the northern hemisphere, although this can vary slightly depending on the climate and altitude. In France, the season often starts in March and can extend until June in some mountainous regions.

2. Harvest Size: The recommended size for harvesting morels is generally when they measure between 5 and 10 cm, although this can vary according to personal preferences and culinary uses. A 10 cm morel is already considered relatively large.

3. Harvesting Method: Cutting the morel at the base with a clean knife is indeed recommended to preserve the mycelium and promote future fruiting. This practice is crucial for the sustainability of harvesting sites.

4. Harvest after watering: It is true that morels absorb a lot of water and become fragile after rain. Moreover, they can deteriorate more quickly, which reduces their taste quality.

After harvest:

1. Post-Harvest Preparation :

   • Morels must be handled carefully after harvesting. They should be placed in baskets or cloth bags to allow air circulation, thus preventing condensation and premature spoilage.
   • They must be cleaned quickly but gently. Avoid soaking them in water; a light brushing or a quick rinse under water is sufficient. Morels are porous and absorb a lot of liquid, which can alter their texture and taste.

2. Drying and Preservation :

   • Morels are better preserved when dried, a traditional and effective method to extend their shelf life. Drying also helps to concentrate their flavor. They can be dried in the open air or at a low temperature in an oven or a dehydrator.
   • Once dried, morels should be stored in a dry and dark place, ideally in airtight jars.

 

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8. Conclusion

Cultivating morels is an exciting challenge that, when well mastered, offers you the satisfaction of harvesting fresh, tasty, homemade mushrooms. With the right techniques and suitable tools, you can turn this adventure into a rewarding success.

 

⚠️ Precautions

Morels must be cooked. They are toxic when raw.

If this is the first time you are eating this species, it is best to start with a small amount to check for possible allergies, even after cooking.

Allow about 10 minutes of cooking time in the pan or pot for proper cooking.

 

❓ Frequently Asked Questions

Is it normal for my mycelium to be brown?

The morel mycelium goes through different stages of maturity, which gives it white, orange, and then brown colors.

Should I water my crop?

Being rather a winter crop, the soils are generally naturally moist. Two periods must be taken into account: before inoculation, the soil must be well moist for a good start of the mycelium, and in spring, during the warming of the soils, it is often necessary to add water to maintain soil moisture.

Does it grow back every year?

No. Since it is a saprophytic variety, it decomposes dead matter and does not form mycorrhizae with the surrounding trees. After fruiting, the morel mycelium is weakened. It is also quite sensitive to heat and dryness, so it generally does not survive the summer unless the environment remains cool and moist.

Is it possible to grow them indoors?

It is possible, and it has already been done in Denmark. However, morel cultivation outdoors is already relatively complex and experimental, and indoor cultivation is even more so. The difficulty lies less in the colonization of a substrate by the mycelium than in the technical conditions necessary for its fruiting.

Do cultivated morels taste the same as wild morels?

Yes, morels cultivated outdoors can be just as tasty as those harvested in the woods. The flavor depends on the quality of the soil and its richness in organic matter. Excessive watering or rain during fruiting can diminish the taste of the morels. For better preservation and taste, do not harvest morels immediately after rain.

Is it compatible with other crops in the vegetable garden?

Yes. Morel mycelium mainly establishes itself from October to December, and is harvested from February to May. Morel mycelium feeds, among other things, on the dead roots of cultivated plants.

I have acidic soil, will this work?

No, morels need a basic soil. You will need to add lime or calcium carbonate to raise the pH above 7 before introducing the mycelium.