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    Spawn Magic Master's Mix Gourmet Mushroom Substrate

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    Spawn Magic Master’s Mix (aka fast-fruiting mix) provides an ideal substrate nutrient mix for most wood-loving Edible and Gourmet mushrooms, hydrated to 60% moisture and sterilized. The bag’s injection port allows contamination-free inoculation via liquid culture syringe.

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    Cultivating Edible and Gourmet mushrooms has never been easier! Spawn Magic Master’s Mix is a blend of 50% soy hulls and 50% sawdust, mixed and hydrated to 60% moisture before complete sterilization. This nutrient combination is carefully formulated to promote rapid colonization and multiple flushes in wood-loving Edible and Gourmet mushroom species.

    Master’s Mix comes in a sturdy 5 lb plastic bag which features an injection port for easy inoculation with liquid culture syringe. Grow healthy mushrooms without exposing your substrate to outside contamination, and without the need for elaborate sterilization equipment.

    Ideal for Many Edible and Gourmet Mushroom Species

    The nutrient blend of Master’s Mix substrate is ideal for a wide variety of popular mushrooms. Many Edible and Gourmet mushrooms are wood-loving species and most will thrive in Master’s Mix, such as Oyster, Lion’s Mane and Reishi mushrooms. Each mushroom is different, though; do your research first to understand your mushroom’s particular needs.

    Rapid Colonization and High First and Second Flush Yields

    Master’s Mix substrate is carefully hydrated to 60% moisture to promote rapid colonization with mycelium; heavy first and second flushes of mushrooms are common.

    Injection Port for Easy Inoculation

    This sturdy substrate bag includes an injection port, enabling easy inoculation by liquid culture syringe. This reduces the risk of outside contamination and the need for elaborate sterilization equipment, making it ideal for mushroom cultivation novices and casual hobbyists.

    Saves Time and Space with Large Flushes

    Rather than several mediocre flushes, Master's Mix is formulated for fast and thorough absorption of nutrients, leading to a large first and second flush before the block is exhausted. This saves you time and effort, freeing up space for the next high producing mushroom block to take over.

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    Add colonized grain spawn in a still-air box or in front of a flow hood to prevent contamination. Grain spawn will colonize faster and produce better yields in the long run, but requires additional steps and care to prevent contamination during transfer. Use approximately 10-15% grain spawn by weight to inoculate a 5 lb block. 

    For some species, direct inoculation with a liquid culture is possible - we recommend this as a possibility only for lion’s mane or reishi mushrooms, but spawn to bulk transfers are still recommended for most species. 

    The approximate time from inoculation to the first flush and harvest may vary greatly depending on species, strain, and temperature/lighting of the environment.

    After the first harvest, the block should be soaked in water for 5 hours, and then allowed to drain before placing into a fruiting environment once again. Fruiting a second and sometimes a third flush is standard practice, but yields will decrease by about 50% per flush. 

    Alternatively, after the first harvest, the block may be carefully broken apart and used for propagation as you would in grain-to-grain transfers.


    • Ingredients: 50% soy hulls, 50% hardwood sawdust, water
    • Weight: 5 Lbs
    • Moisture Content: 60%
    • Sterilized and ready to use
    • Packaging: Unicorn XLS-T Bag with 0.2 Micron Filter & Injection Port


    SpawnMagic Masters Mix 5lb