Sterilized Master's Mix Bag 5 lbs
Sterilized Master's Mix Bag 5 lbs is backordered and will ship as soon as it is back in stock.
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Description
Description
Our Sterilized Master's Mix Bag is 5 lbs of pre-hydrated, pH-balanced hardwood sawdust and soy hull substrate, pressure-sterilized at 250°F (15 PSI) for 3.5 hours and sealed in a 0.5-micron filter patch bag — ready for your colonized grain spawn.
It's the same optimized substrate we use in our own grow blocks. There's no mixing, hydrating or sterilizing to do: add your colonized grain spawn, re-seal the bag and let your mycelium run. Master's Mix is the go-to substrate for lion's mane, oysters, pioppino, chestnut, shiitake and other wood-loving gourmet and medicinal mushrooms.
- 5 lbSterilized substrate
- 250°F15 PSI
- 3.5 hrsSterilization
- 0.5 µmFilter patch
- 12–13Bags per 5 lb spawn
Why growers choose Master's Mix
- No prep – Pre-hydrated, pH-balanced and already sterilized, so you skip the mixing, hydrating and pressure cooking.
- Nutrient-dense – The hardwood and soy hull blend carries far more nutrition than coir-based bulk substrate, which supports bigger flushes.
- Properly sterilized – Pressure-sterilized at 250°F (15 PSI) for 3.5 hours.
- Sealed and filtered – Packed in a heavy-duty 14A bag with a 0.5-micron filter patch.
- Proven in-house – The same substrate we use in our own grow blocks.
What's included
- One 5 lb bag of sterilized Master's Mix (hardwood sawdust and soy hull blend), pre-hydrated and pH-balanced, sealed in a 14A 0.5-micron filter patch bag
What is Master's Mix?
Master's Mix is a nutrient-dense substrate made from hardwood sawdust and soy hulls — the standard blend for wood-loving gourmet and medicinal mushrooms. Because it's sterilized rather than pasteurized, it can carry far more nutrition than coir-based bulk substrate. The trade-off is that it must stay sealed and be handled with sterile technique: it is inoculated inside the bag with colonized grain spawn, not mixed in an open tub.
How to use your Master's Mix bag
- Work clean. Work in front of a flow hood or inside a still air box.
- Add your spawn. Open the top of the bag and add your colonized grain spawn.
- Re-seal and mix. Heat seal or fold and clip the bag closed, then shake gently to distribute the spawn.
- Incubate. Keep the bag at 70–75°F in the dark until the block is fully colonized.
- Fruit. Cut the bag open and introduce fresh air and indirect light to trigger fruiting.
How much grain spawn do I need? A single 5 lb colonized grain spawn bag will inoculate roughly 12–13 of these Master's Mix bags. Because the substrate is fully sterilized, a lighter spawn rate works well, though a heavier rate will colonize faster.
Keep it sealed. Unlike coir-based bulk substrate, which is used in non-sterile conditions as a tub mix or casing layer, Master's Mix is not meant to be exposed to open air or mixed in an unsterile tub. Doing so invites contamination and defeats the purpose of sterilization. Add your spawn directly into the bag, let it fully colonize, then fruit by cutting the bag open or moving the colonized block to a clean fruiting chamber.
What can you grow?
Master's Mix is built for wood-loving species, including:
- Lion's mane
- Oyster mushrooms — blue, gold, pink, king and more
- Pioppino and chestnut
- Shiitake, reishi, maitake and other hardwood-loving varieties
Step-by-step: how to inoculate your Master's Mix bag with colonized grain spawn.
Specifications
| Specification | Detail |
|---|---|
| Weight | 5 lbs |
| Substrate | Master's Mix: hardwood sawdust and soy hull blend |
| Preparation | Pre-hydrated and pH-balanced |
| Sterilization | Pressure-sterilized at 250°F (15 PSI) for 3.5 hours |
| Bag | Heavy-duty 14A bag with 0.5-micron filter patch |
| Spawn needed | One 5 lb colonized grain spawn bag inoculates about 12–13 bags |
| Incubation | 70–75°F, in the dark |
| Colonization | About 2–4 weeks for most wood-loving species; shiitake and reishi take longer |
| Best for | Lion's mane, oysters, pioppino, chestnut, shiitake, reishi, maitake |
Pair it withColonized grain spawn to inoculate, and a flow hood to keep your transfers clean. Growing in a monotub instead? Use coir-based bulk substrate.
FAQ
What is Master's Mix made of?
Master's Mix is a blend of hardwood sawdust and soy hulls, pre-hydrated and pH-balanced. Each 5 lb bag is pressure-sterilized at 250°F (15 PSI) for 3.5 hours and sealed in a 0.5-micron 14A filter patch bag.
How do I inoculate a Master's Mix bag?
Work in front of a flow hood or inside a still air box. Add your colonized grain spawn into the bag, re-seal it and shake gently to distribute the spawn. Keep the bag sealed and incubate until fully colonized — never mix it in an open tub.
How much grain spawn do I need per bag?
One 5 lb colonized grain spawn bag inoculates approximately 12–13 Master's Mix bags. Since the substrate is fully sterilized, a lighter spawn rate works fine, but more spawn per bag will colonize faster.
What mushrooms can I grow with it?
Master's Mix is ideal for wood-loving gourmet and medicinal species, including lion's mane, all oyster varieties, pioppino, chestnut, shiitake, reishi and maitake.
Can I use Master's Mix in a monotub or mix it in open air?
No. Master's Mix is a sterilized substrate meant to stay sealed and be inoculated with sterile technique. Exposing it to open air or mixing it into a tub invites contamination. For monotubs and casing layers, choose a coir-based bulk substrate instead.
How long does colonization take?
Most wood-loving species fully colonize a 5 lb block in about 2–4 weeks at 70–75°F, with slower species like shiitake and reishi taking longer. Timing varies with strain, spawn rate and temperature.
Do you offer wholesale pricing?
Yes. For orders of 10 bags or more, contact us for wholesale pricing.
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