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Posted October 14

Sterilized Rye Berries - Grain Spawn

Starting at: $7.95

Please Choose:

Sterilized and prepared mushroom grain spawn substrate (1 lb.) in a gusseted autoclave bag with filter patch and self-healing injection port. Shroom Supply grain spawn is composed of 100% USDA certified organic rye berries which is widely regarded as the highest quality grain for spawn production and is the industry standard for mushroom cultivation. The substrate is free of any additives or chemicals and is recommended for use with our pre-pasteurized mushroom compost.

Once colonized with mushroom mycelium, we recommend using the colonized grain spawn to inoculate a bulk substrate, like our premium pre-pasteurized mushroom compost. We recommend spawning two pounds of our grain spawn to five pounds of our compost. Alternatively, the colonized grain spawn can be transferred to more sterilized grains to promote further propagation of the mushroom mycelium (also known as a grain to grain transfer).

We prepare our organic rye berry grain spawn by thoroughly rinsing the grains, then soaking them for 18 hours in a gypsum-fortified water bath to ensure optimal moisture and mineral levels. Immediately after the soak, the rye is simmered for 10 minutes in distilled water. The rye berries are then sterilized at 15 PSI in a lab-grade autoclave for a complete 120 minutes.

Our grain spawn comes heat-sealed in a sterile, filter-patch mycobag with injection port and can be stored at room temperature for up to 14 days before use. If longer than 14 days is needed, the grain can be stored in a clean container in the refrigerator for up to six weeks. Do not freeze.

All sterilized grain spawn will come packaged in individual 1 lb. bags, regardless of quantity ordered.

Made to order, usually ships within 2 business days.

Instructions: How to inoculate sterilized grain bags

Adam K.
5 of 5 Stars
A+ I’ve been into mycology since ‘99 and this is the VERY FIRST TIME that rye has worked for me. It’s usually overly wet takes forever, and then contams. So millet/WBS was always my medium. These rye bags are killin’ it! I made an LC in a jar and used Shroom Supply’s bags as a trial run. 5 days later, all surfaces are covered and pulling inward! Great stuff! I will order more of these!!!
Rene I.
5 of 5 Stars
This Is the Best! went with the MW Grow kit brand 2 grows back and those bags were a waste of "TIME & and Money"! mostly TIME... big mistake! i wont order from anywhere but Shroom Supply in the future!!!
Rene I.
5 of 5 Stars
Best BAGs Out There, left to try other brands but they failed! So Im back and never leaving... Sorry Shroom Supply!
Erik C.
5 of 5 Stars
This grain spawn works great. No issues with contamination or colonizing. This company is professional and knows what they are doing. We will continue to use this website for future orders. Fast shipping and good communication. We would recommend others here who are in search of mushroom supplies. 5 stars.
Christopher O.
5 of 5 Stars
I purchased about 5 of these bags and only used 2 to start. Im running an experiment right now and have knocked up another bag 4 months later! So far so good knocked up maybe a week or less ago. I didn't know if there was enough moister or what not left in the bag but it looks like the spores like the home. I also kept them wrapped up and in a bin stored in my closet to try and keep as much contaminated off the bag and kept the FILTER as much as i could away from open air etc. I know have a pc so i made my first jars of grain with popcorn so i won't need to buy these bags as often anymore but def worth the 7$ if its your first time growing great way to have a successful first run and many more! Love this site so much!
Kenneth B.
5 of 5 Stars
I had a grain bag busted opened when I got it emailed the next day I had a new one on the way , that’s customer service at its best thanks Shroom supply I never order any where else
Mary H.
5 of 5 Stars
Fast Shipping, great product, and no contamination. Would definitely buy again!
Kelob B.
5 of 5 Stars
Shipping was fast and organized. This is my first attempt at Spawning, syringes on the way! Looking forward to trying it out.
Jacob C.
5 of 5 Stars
Was a little skeptical ordering these online . But for such a great price I though lets give it a try . Shipping was lightning fast to the Midwest . Extremely happy with service . Will update on colonization success.
Zachary F.
5 of 5 Stars
Literally the best company, have gone above and beyond for me multiple times through the ordering process always speedy shipping, replying to emails with questions I’ve had. You guys rock seriously, and the grain spawn is great quality always fresh.
Anne D.
5 of 5 Stars
These guys are awesome. Never had any problems with the grain spawn. Always fresh and fast shipping on product. Would recommend such a time saver.
William H.
5 of 5 Stars
WOAH!! Y'all...........Fastest shipping times i've ever seen. These spawn bags are top quality. I will never use anyone else other than Shroom Supply. You all have the best customer service and are very friendly and informative. I can tell you really care about this hobby/passion and it shows in your products and service. Thank you, Shroom Supply!
David G.
5 of 5 Stars
Quality product! The rye bags with the injection port...SO GOOD! These guys actually thought this through. I saw signs of growth only 5 days after injection! I am definitely ordering again! If anyone has any doubts you have no worries here. Shipping was fast and the price is amazing too! Thank you!
Marshall U.
5 of 5 Stars
Luved them... 1st 2 times I tried to grow anything I had mold problems.. ordered the bag it came fast.. now I'm ordering the rest of wut I need to fruit.. best site ever
David H.
5 of 5 Stars
These bags are WAY WAY better than any other pre-made spawn jars or bags I have ever used. Great price & Super fast shipping. Top Quality....Shroom Supply is my go-to for all my myco needs.
andrew D.
5 of 5 Stars
If you have even the slightest doubt in your own grain prep and want to ensure that nothing goes wrong with your prized genetics, or plan a grain to grain transfer with one of you're favorite species then look no further for peace of mind and quality. Even experts can benefit from the ease and trusted sterilization that is Ryans perfected method. I have yet to see a comparable product with this high of quality in packaging and product on any site I've tried. Not to mention the customer service and shipping is outstanding and fast! Ryan is the man! Worth every penny! MushLove
Gucci mane
5 of 5 Stars
A bit pricey, but very pleased with this product. Great costumer service as well.
5 of 5 Stars
Extremely fast shipping I ordered it on the weekend and got it in 2 days great stuff yall
5 of 5 Stars
The discreet package was delivered on time as expected.
Zac S.
5 of 5 Stars
These guys are the best in the business, no doubt about it! Perfect product every time, with extremely fast shipping. Like they say if they don't have you don't need it 100% true.
5 of 5 Stars
By far the best bags out there. These guys do it right. If you want the best you have found it. Dont waste any more money on bags that are trash. Buy these bags and do yourself a favor!!!!!!!
5 of 5 Stars
Ordered two lbs. of grain spawn and the quality of the product is up there with the best. Discreet shipping, and my package was delivered one day early!
5 of 5 Stars
Please don't be fooled by the other pricey gimmicks. This is thee ONLY company I will Ever order from. It is a miracle to have found you guys, and I will NEVER Switch up. Was a straight BRF guy until Ryan recently and very EASILY changed my mind. Quality prodicts. And even better, personalized and Very Knowledgeable help and information if ever needed. That was my selling point to be honest. Thanks again
5 of 5 Stars
I've been using these grain bags for over a year now and have consistent success every time. If you're trying to cultivate mushrooms this is the way to go. Thanks shroomsupply!
R Dubya
5 of 5 Stars
FAST shipping. Easy to use. I've gone through 5 bags so far with no contams. Great buy, for sure.
5 of 5 Stars
Received within 2 BD of ordering; bought 12 lbs. Immediately used 10 bags to inject with LC and they are rocking; used 2 more a few days later for grain to grain and that was the fastest colonization I've ever seen (Old World Blue Oyster, about 5 days). Thanks for a great product!
5 of 5 Stars
Wow super fast service and very friendly the bags are packaged nicely and very well made I don't forsee any issues and I will definitely be ordering again!
Frank Hernandez
5 of 5 Stars
I had previously tried similar sized / featured rye spawn bags from 4 other vendors -- no need to mention their names because if you are reading this, you have found the diamond in the ruff! These bags not only arrived the fastest, but they also have THE BEST QUALITY and craftsmanship put into them. Between the fast shipping, quality and well-assembled bags, speedy colonization rates... this is the only place I will ever buy my spawn from. If skeptical, YOU WILL NOT BE DISAPPOINTED. I only rate 5 stars because I cannot rate more! lol. The best bags out BY FAR! Look no further.
Jeff Keith
5 of 5 Stars
Not only a great product but these people have hyper speed shipping ! Don't waste time and money with other companies, The Shroom Supply is the best !
5 of 5 Stars
You will not regret it! Just be sure to loosen up the bag (read directions on the page) working on my next order now :D
mr. Anderson , newbie
5 of 5 Stars
wow, I mean wow, fastest shipping iv ever had . ordered on Thursday and at my door on Saturday. iv got to say also I am about 4 states away to. haven't started research as yours came before the spores so we will see. also thanks for the free syringe, clean and dry , I am sure ill find a use for it. thanks guys and if all goes well ill be ordering again soon . so far, very happy.
the dude
5 of 5 Stars
What else can be said.These guys know what they are doing and from what I can see first hand is the best product at the best price.Along with fast delivery, put all that together and you've got this place.
5 of 5 Stars
This product is amazing and very simple even for new newbies. I ordered five grain bags from shroom supply and five from another vendor. Two out of the three bags from the other vendor have decent looking mycelium. The other three have either contaminated or have wet spot and have stopped. All five of the shroom supply bags are thriving and have the thickest, healthiest looking Growth. I cant wait for the next step! Thanks shroom supply!
5 of 5 Stars
These bags went from being great to PERFECT. Shroom Supply just started including injection ports on all of their rye bags... and they didn't raise the price! I LOVE LOVE LOVE the injection ports. That make inoculation of the bags so easy and they ease my mind about contamination! Thank you guys!
5 of 5 Stars
Great product, produced amazing results, 10/10 would recommend.
5 of 5 Stars
Although I'm fairly new to the hobby I've always have had good service and fast delivery. Next time I'm going to order these if for no other reason than simple ease of operation.
5 of 5 Stars
nothing but good things to say about you guys. you always ship fast, have great prices, and products are always of superb quality. i buy these sterilized rye bags from you on the regular and they always work great. i usually see the first signs of growth in 2 or 3 days and they are always fully colonized within a month. keep doing what you're doing!
5 of 5 Stars
Worked out perfectly for me! I was ordering from another popular vendor but the bags I got from him consistently had wetspot which indicates improper preparation technique to me. The rye grain I have gotten from this company always appears to be prepped to professional standards and always colonizes quickly and without issue. I am now a loyal customer to Shroom Supply and have dropped the other vendors.
AM Student
5 of 5 Stars
I was a scholarship student with a well-known and widely respected spawn making program and this rye grain appears to be perfectly prepped in accordance to what I was taught in the program. I have since bought all the equipment to prep my own grain spawn but I will certainly recommend your company to anyone who need their grain spawn made up for them. Great job guys! I will also post a positive review for you on the forums!
5 of 5 Stars
Good product my only gripe is they don't have self healing injection points or a double layered designated point, would be perfect if those where added,but still worked great
5 of 5 Stars
very fast shipping will use this company again for sure
5 of 5 Stars
These bags are professionally packaged. You can tell that this company really puts time into their products. I give them 5 stars and I will definitely be back.
Jack Turnbull
5 of 5 Stars
Fast shipping... thank you for the good service. Regards.
Teddy S.
5 of 5 Stars
this product colonized twice as quickly as a rye bag i ordered from another company. i will report back when i find out what kind of yield i get off it.
roger norwick
5 of 5 Stars
Best I've Seen anywhere great quality awesome price quick shipping