How to Use Grain Spawn

How to Use Grain Spawn

Grain spawn is already fully colonized and ready to be mixed with substrate. This is the fastest way to move into fruiting without having to inoculate and wait for grain to colonize.

Step-by-step

  1. Check the bag
    Make sure the grain is fully colonized. It should be solid, white, and evenly covered.
  2. Break it up
    Break the grain apart inside the bag until it’s loose and easy to mix.
  3. Prepare your substrate
    Have your CVG or Masters Mix ready before opening the spawn.
  4. Mix with substrate
    Combine the spawn and substrate evenly. A common ratio is around 1:1.
  5. Load into your bag or container
    Level it out and lightly pack it into place.
  6. Let it colonize
    Store at room temperature (68–75°F) until the substrate is fully colonized.
  7. Introduce fruiting conditions
    Once colonized, allow fresh air exchange and proper humidity to begin fruiting.

Important Notes

  • Only use fully colonized spawn
  • Work clean, but full sterile conditions are not required
  • Match your substrate to the species (CVG vs Masters Mix)
  • Avoid direct sunlight during colonization
  • Handle the spawn gently when breaking it up

Common Mistakes

  • Using spawn that isn’t fully colonized
  • Mixing unevenly with substrate
  • Using the wrong substrate for the species
  • Letting the substrate dry out
  • Introducing fruiting conditions too early