What's the difference between the half-pint jars and grain jars that we offer?
Let's be real- we have quite a few different substrate jars that we offer. But what is the main difference between them?
Half-Pint Jars (BRF jars)
The main components of our half-pint BRF jars are brown rice flour and vermiculite. The top 1/2 inch or so of the jar is just vermiculite; this acts as a protective layer, preventing any contaminants from getting inside. We recommend these for beginners-they are the easiest to inoculate successfully. We sell them in 6 and 12-packs, so you have some room for error, too! Although they are less susceptible to contamination, brown rice flour is not as nutritious as whole grains, making the anticipated yield smaller than it would be if you were using a whole grain spawn. The most popular way to fruit half-pint jars is in a humidified chamber; our classic jar grow kits are all examples, as well as a couple of our Ecosphere models! Although they can be fruited using other methods, they perform best fruiting individually in a sealed, humid chamber with consistent fresh air exchange. This is the classic PF Tek method — read the history and pros and cons of PF Tek.
Grain Jars
Grain jars are exactly what they sound like- sterilized whole grains, with just a little bit of pH stabilizers to speed up colonization. Whole grains are the ideal food source for mycelium, making yields much larger than you'd expect with the half-pint jars. Although it sounds perfect, the lack of protective materials/additives makes the grains much more susceptible to contamination after inoculation. For best results, cultivators use liquid culture or colonized agar; this skips the germination process, lowering the colonization times and chances of contamination drastically. Grain jars are most often used in a bulk or 'monotub' grow; once fully colonized, you break up the grains and combine them with a non-nutritious bulk substrate to increase the surface area. The mushrooms will then fruit from a bed, similar to how they grow in nature! Our monotub grow kits, Ecosphere systems, and All-in-One bags use this model! Although it should be pretty smooth sailing once you get the spawn and substrate combined, it's possible that contamination could creep into your chamber, potentially costing you the entire grow. We recommend giving grains a try once you feel you have mastered cultivation with the half-pint jars and have a good understanding of the components necessary for a successful grow. Our complete guide to grain spawn is a good next step.
Half-Pint Jars
Pros:
- Not too difficult to get inoculated
- Room for error
- Affordable ingredients
- Mushrooms!
Cons:
- Lower yield
- Can require more materials/accessories
Grain Jars
Pros:
- High yield- lots of mushrooms!
- Easy to find pre-sterilized spawn and substrate
Cons:
- More difficult to inoculate successfully
- Little room for error
- May require more room in your growing area