Pasteurized Bulk Substrate


We recommend the default substrate as it comes out to be 25% Coco Coir, 25% Horse Manure, 25% Shredded Straw, 25% Vermiculite, plus the non-volume adding 5% Gypsum.

The default substrate is an ideal mixture that has been properly hydrated by bringing to field capacity, mixing, and then pasteurized. Comes in one filter patch bag. The coco coir is ideal for creating a fluffy substrate that has a better micro environment than horse manure alone.. The horse manure and straw increases the ash (minerals) and nitrogen content ensuring a higher biological efficiency than just coir. Vermiculite increases the water carrying capacity of the substrate along with making it more fluffy aiding to the micro-climate in the substrate.

Made the day you order and shipped as soon as possible.

About the substrate:

All variations of substrate has, by volume, 5% Gypsum (calcium sulfate) added.
All material is individually hydrated to field capacity before being mixed with the other substrate. It is done in this order to ensure that the substrate has the highest stable water content, which is important because it has been shown that available water during colonization and fruiting is one of the biggest factors when it comes to yield.

The individually hydrated substrates are ran through a trommel if appropriate and then mixed in the desired ratio using a cement mixture to ensure all substrate material is evenly distributed and that it is lose and fluffy, creating the ideal micro-climate for rapid colonization once the grain spawn has been added.

About the Coco Coir:
Coco coir is soaked in water for 24 hours. This long soak helps to ensure that it is properly hydrated. If it is not soaked for a long period, it can continue to absorb the water and become less than field capacity during shipping.

After the soaking it is ran through the trommel to ensure that it mixes properly with the other substrates and to remove any chunks of unwanted materials.

About the Shredded Straw:

The shredded straw is made from the smaller golden wheat straw and is processed to be approximately 1/2 inch in length. It is then brought to field capacity by soaking for at least 24 hours.

About the Horse Manure:
The horse manure is collected in a way to ensure that it is free of unwanted debris. It is aged outside in the sun with frequent watering to reduce ammonia and urea, and yield desirable nitrogen sources by growth of firefang (actinomycetes).

It is then ran through a 1/2 inch trommel to break it apart to ensure it mixes evenly with the other substrates.

Before it is mixed with the other substrate It is brought to field capacity by a long soak.

About the Vermiculite:

The vermiculite is Grade #2 from Therm-o-Rock. The size that is most suited for holding moisture and keeping the substrate loose and fluffy. It is brought to field capacity before being mixed with the other substrates.

Recommended Spawn Ratio:
3 lbs of grain spawn or 5 lbs of bulk substrate. You can buy sterilized grain in a filter patch bag with an injection port HERE

The 3lbs/5lbs ratio ensures a very rapid colonization rate and further increases the mineral and nitrogen content. By volume, this is about a 1:2 ratio. Any more spawn and the substrate structure starts to become less than ideal, and any less will of course result in slower colonization rates. you can use a 1/4 ratio without any risk of contamination, but colonization time and yield will be lower.

Note: If desired and requested by email first, we can also add Sphagnum peat moss to your substrate.

Buy Sterilized Grain HERE

Buy Casing Material HERE

Buy Complete Monotub Kit HERE

Buy Monotub Replacement Kit HERE
The monotub replacement kit comes with a 7 lbs bag of bulk substrate, & 3 lbs of sterilized grain.