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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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Justin Thyme
5 of 5 Stars
Have yet to try. Just wanted to thank you guys. I ordered a bunch of stuff and received a free sample Bag. Will start the "test" tomorrow. Update to come!!
5 of 5 Stars
This is by far the best bought bulk substrate I've had the pleasure of growing/experimenting with. I've tried numerous times to duplicate the substrate and results to no avail. Whatever it is you guys are doing is working, so keep it up. Also, I have yet to experience any contamination problems as well when using this, so pasteurization is superb, unlike many other mycology suppliers out there. I will vouch for this bulk substrate any day. -Clay
5 of 5 Stars
This compost works really well top notch and shipping is super fast A+++ for sure
5 of 5 Stars
Just wanted to say thanks for the speedy shipping, ordered on Friday, got my packages on Monday. Can't beat that. Also, great quality products as well. Already more results in less than 24 hours, than in a month using other products. Will be in contact soon to get more for sure. Thanks a lot!!
5 of 5 Stars
Your substrate is top-notch and is all I ever use.
5 of 5 Stars
Great product and super fast service. Return customer, bought TONS of substrate literally!

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