Substrate Preparation Protocol

Standard Operating Procedure for bulk substrate pasteurization.

CVG Substrate Preparation

For commercial-grade consistency and optimized mycelial run times, the CVG (Coir, Vermiculite, Gypsum) method remains the industry standard. Below is the refined protocol emphasizing efficient brick breakdown and precise hydration.

CVG Formula Ratios

Step-by-Step Protocol

1. Initial Softening

Place the dry 650g coco coir brick into a heavy-duty, heat-resistant 5-gallon bucket. Pour 0.5 quarts (approx. 500ml) of boiling water directly onto the brick. Cover for 5–10 minutes. This pre-softens the compressed fibers, allowing you to break the brick into a coarse meal with a sterilized chisel or heavy spoon without creating dust or requiring excessive physical force.

2. Dry Ingredient Integration

Once the brick is broken down, add 2 quarts of vermiculite and 1/2 cup of gypsum. Mix thoroughly while dry to ensure the gypsum is evenly distributed throughout the coir fibers.

3. Primary Hydration & Pasteurization

Add the remaining 3 to 4 quarts of boiling water.

• Pro Tip: Start with 3.5 total quarts (including the initial 0.5) and adjust based on the specific brand of coir, as absorption rates vary. Immediately seal the lid tightly to retain heat.

4. The "Bucket Tek" Heat Cycle

Allow the bucket to sit undisturbed for 6 to 24 hours. The internal temperature must remain above 140°F (60°C) for at least 1.5–2 hours to effectively pasteurize the substrate while preserving beneficial thermophilic bacteria that help resist contamination.

5. Field Capacity Verification

Before inoculation, verify the moisture content.

• The Squeeze Test: Take a handful of substrate and squeeze hard.
• Target: Only 2–3 drops of water should escape. If it runs like a faucet, it is over-hydrated; add a small amount of dry, vermiculite to compensate.