Ultimate ½ Pint Substrate Jars (12-Pack)
Ultimate ½ Pint Substrate Jars (12-Pack) is backordered and will ship as soon as it is back in stock.
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Description
Description
Ultimate ½ Pint Substrate Jars are sterile, ready-to-inoculate PF Tek jars made with our BRF recipe: organic brown rice flour, vermiculite, mineral water, liquid worm castings and bee pollen. You get 12 jars, pressure-sterilized and made fresh the day your order ships.
Each 8oz glass jar is topped with a dry vermiculite layer and capped with a lid pre-drilled with four inoculation holes. Add your spore syringe or liquid culture and incubate — no mixing, packing or pressure cooking on your end. It is still the simplest way to learn sterile technique and grow your first cakes.
- 12½ pint jars
- 8 ozGlass jars
- 120 minAutoclave sterilized
- 4 holesPre-drilled lid
- 1–1.5ccSpores per jar (2cc LC)
Why growers pick our BRF jars
- Enriched recipe – Liquid worm castings and bee pollen are added to the classic brown rice flour and vermiculite mix.
- Sterilized in-house – Every batch is pressure-sterilized for 120 minutes in our commercial autoclave.
- Made fresh to order – Jars are made the same day your order ships — not pulled from a warehouse shelf.
- Contamination barrier – A dry vermiculite layer on top helps filter what gets in through the inoculation holes.
- Packed to arrive intact – Each jar is foil-wrapped and bubble-packed for shipping.
- Refined over 15 years – The same recipe we have been tuning since we started making jars.
What’s in each jar
- Organic brown rice flour (BRF)
- Vermiculite
- Mineral water
- Liquid worm castings
- Bee pollen
- Dry vermiculite top layer
How to use them
- Store until you’re ready. Keep jars in the fridge for up to 3 months. Let them come to room temperature before you inoculate.
- Work clean. Wipe down your workspace, sanitize the jar lids and flame-sterilize your needle.
- Inoculate. Inject 1–1.5cc of spore solution or 2cc of liquid culture per jar, split across the four holes. Cover the holes when you’re done. Not sure how many syringes to buy? Use our syringe calculator.
- Colonize in the dark. Keep jars somewhere clean, dark and steady, ideally in the low-to-mid 70s °F. They don’t need light or humidity while they colonize.
- Birth and fruit. Once a jar is fully white, birth the cake into a fruiting chamber — or use the colonized jars as spawn for a bulk grow.
New to jars? Our guide to growing mushrooms in substrate jars walks through the full PF Tek process, and how to store substrate jars covers where to keep them while they colonize.
Specifications
| Specification | Detail |
|---|---|
| Quantity | 12 jars |
| Jar | ½ pint (8 oz) glass canning jar |
| Substrate | Organic brown rice flour, vermiculite, mineral water, liquid worm castings, bee pollen |
| Top layer | Dry vermiculite |
| Lid | Pre-drilled with 4 inoculation holes |
| Sterilization | Pressure-sterilized 120 minutes in a commercial autoclave |
| Made | Fresh, the day your order ships |
| Packaging | Foil-wrapped and bubble-packed |
| Storage before use | Refrigerate, up to 3 months |
| Inoculation | 1–1.5cc spore solution or 2cc liquid culture per jar |
Also availableJust want to try a few? The 6-pack has the same jars.
Ready for bigger yields?Sterile grain jars colonize into spawn you can move into a monotub. Read half-pint jars vs grain jars to see which fits your grow.
FAQ
What is PF Tek?
PF Tek is the classic beginner method of growing mushroom cakes in small jars of brown rice flour and vermiculite. You inoculate the jars, let them colonize, then birth the cakes into a fruiting chamber.
Are the jars sterile?
Yes. Every jar is pressure-sterilized for 120 minutes in our commercial autoclave, then foil-wrapped so it arrives ready to inoculate.
How much should I inject into each jar?
Use 1–1.5cc of spore solution or 2cc of liquid culture per jar, split across the four pre-drilled holes.
How long can I store the jars before using them?
Up to 3 months in the refrigerator. Let them warm to room temperature before you inoculate.
What makes these different from a basic BRF jar?
We add liquid worm castings and bee pollen to the standard brown rice flour, vermiculite and water recipe, and top every jar with a dry vermiculite barrier.
What do I need to fruit the cakes?
A humid fruiting chamber with fresh air and indirect light. Our classic jar grow kits include everything you need to fruit jars.
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