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Pre-Pasteurized Mushroom Compost

Starting at: $5.95

Please Choose:

Pre-pasteurized premium bulk substrate mushroom compost in a gusseted autoclave bag with filter patch. Shroom Supply mushroom compost is specifically formulated for growing mushrooms. It is free of any additives or chemicals and is to be used in conjunction with our mushroom grain spawn.

This choice bulk substrate is composed of five main ingredients including an organic compost specifically designed for mycological use, composted horse manure, organic coconut coir, vermiculite, and gypsum. This diverse blend of unique ingredients provides the perfect amount of nutrition for optimal mycelial growth, making it the ideal growing medium for mushroom cultivation.

Our premium mushroom compost comes pre-pasteurized and hydrated to the perfect moisture content, making it ready to use right out of the bag. Simply add colonized grain spawn, mix, and add to your fruiting chamber or grow bag. We recommend using two pounds of our grain spawn for every five pounds of compost. Once the substrate is fully colonized with mushroom mycelium, our casing mix can be applied in a thin layer to the top of the substrate. Please note that a casing layer is not required, but rather an optional ingredient that can benefit the growth of certain mushroom species.

This product comes heat-sealed in sterile, filter-patch mycobags and can be stored at room temperature for up to 14 days. If more time is needed, it can be stored in the freezer and dethawed before use.

All mushroom compost comes packaged in 5 lb. increments.

Made to order, usually ships within 2 business days.

Instructions: Bulk Substrate Tutorial

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5 of 5 Stars
This stuff is the best yet and so is the customer service. Let me tell you I ordered a lot of stuff and the box was really in bad shape from UPS. So I had a product that ripped open and I told customer service that UPS played soccer with the box and described the tear in the bag. That's when they sent me a new bag. I am so grateful and can get the show on the road.
5 of 5 Stars
successful results with this stuff every time. only substrate i will use now. primo poop for sure!
5 of 5 Stars
5 of 5 Stars
I used to order my compost from HMC but their product has went downhill from when I was ordering years ago. This stuff is great though. It is a super dark, rich fluffy compost that out performs the other stuff I was using by a long shot! An excellent value for the money, fast shipping, and excellent customer service. KUDOS!
5 of 5 Stars
I haven't used anything else before this, I'm new to the hobby. But my mushrooms seemed to love it! They are located close to me so shipping was fast. Will order again =)
5 of 5 Stars
So, I received some of this substrate as a freebie with a large order. That will not affect my review. I've tried almost all of the bulks out there, and this stuff is the s#!t!! I WILL be buying my substrate from here on out from YOU. It went above and beyond my expectation. Mycelial growth is fast, and no contams. What more can you ask for? Honestly?

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