🌾 How to Make Grain Spawn Starting from Raw Unsterilized Grains

Making grain spawn from raw, unsterilized grains is a fundamental skill in mushroom cultivation. Grain spawn serves as the nutrient-rich base for mycelium to colonize before transferring to a bulk substrate. This guide will walk you through the process of turning raw grains into fully colonized grain spawn, step by step.

🧫 Step 1: Select and Prepare Your Grains

• Choose Your Grains: Common grains like rye, wheat, millet, and oats are ideal for grain spawn due to their nutrient content and ease of use.
• Rinse Thoroughly: Rinse the raw grains under running water to remove dust, debris, and any loose hulls.
• Soak the Grains: Soak the grains in water for 12-24 hours to hydrate them. This step helps prepare the grains for cooking and sterilization.

🔥 Step 2: Cook the Grains

• Boil the Grains: After soaking, boil the grains for 10-15 minutes until they are fully hydrated but not mushy. Overcooking can cause the grains to burst, leading to contamination risks.
• Drain and Dry: Drain the grains and spread them out on a clean surface to dry for 15-20 minutes. The grains should be moist but not wet to the touch.

🧼 Step 3: Sterilize the Grains

• Pack the Grains: Transfer the cooked grains into mason jars or autoclavable bags, filling them about two-thirds full to allow room for mycelium growth.
• Sterilize: Sterilize the grains in a pressure cooker at 15 PSI for 90 minutes. This step is crucial to kill any bacteria, mold, or contaminants that could compete with the mycelium.

🦠 Step 4: Inoculate the Sterilized Grains

• Prepare Your Inoculum: Use a liquid culture syringe, spore syringe, or agar culture to introduce mycelium to the sterilized grains.
• Inoculate in a Sterile Environment: In a clean, sterile workspace, inject the inoculum into the grain jars or bags. Seal them with breathable tape or filter patches to allow gas exchange.

🌡️ Step 5: Incubate the Grain Spawn

• Store in Ideal Conditions: Place the inoculated grain spawn in a warm, dark environment with a temperature of 75-80°F (24-27°C).
• Monitor Colonization: Over the next 1-2 weeks, the mycelium will colonize the grains. Look for white, fluffy growth spreading throughout the jar or bag.

🚨 Tips for Success

• Maintain Sterility: Always work in a clean, sterile environment to avoid contamination. Use gloves, a face mask, and disinfect your workspace.
• Use High-Quality Grains: Ensure your grains are fresh and free from mold or pests before starting the process.
• Be Patient: Mycelium growth takes time. Avoid disturbing the jars or bags unnecessarily during colonization.

📺 Watch the Process in Action

For a visual guide, check out this video on making grain spawn from raw grains:

🛒 Ready to Start Cultivating?

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