Multi Grain Matrix (4 lbs)
Four pounds of sterilized grain pre-spawn, ready to inoculate. 50/50 millet and rye berries, sourced from organic Colorado farms. Soaked, simmered, autoclaved at 123°C for 90 minutes, and sealed with a self-healing injection port.
Millet gives you more inoculation points for faster colonization. Rye holds moisture longer and packs more nutrients. The 50/50 blend gets the best of both. Visible mycelium growth within a week of inoculation.
Once fully colonized, mix with HB4 bulk substrate in a monotub to start fruiting. One bag of grain to one bag of HB4.
Ships in Unicorn 10T-injection port, .2 microns filter patch bags. Inject your spores or liquid culture through the port and let it colonize.
"Visible mycelium within a week. Fastest colonizing grain I've used."Verified Grower
What's in the Bag
50/50 blend of millet and rye berries, sourced from Montana and Colorado farms. Soaked 24 hours, washed, boiled, autoclaved at 123C for 90 minutes. Sealed in a Unicorn Type 14A filter patch bag with self-healing injection port.
Specs & Process
Weight: 4 lbs per bag. Optimal grain moisture for mycelial growth. Millet provides more inoculation points for faster colonization. Rye holds moisture longer and delivers more nutrients. The 50/50 blend gets the best of both.
How to Inoculate
Wipe the injection port with 70% isopropyl alcohol. Inject 3-5cc of spore solution or liquid culture through the self-healing port. Store at 72-78F in a dark area. Visible growth in 5-10 days. Once 30% colonized, break and shake to spread the mycelium.
Shipping & Guarantee
Ships within 24 hours via USPS Priority. Free shipping on orders over $100. If your grain arrives contaminated before you inoculate, we replace it at no cost.
What's Inside
Two grains. One job.
The Blend
50/50 millet and rye. Montana & Colorado sourced. Autoclaved at 123C for 90 minutes.
The Result
Fully colonized grain, ready to spawn to bulk.
Need substrate to finish the grow?
Complete the grow.
Colonized grain needs substrate. Here's what pairs with it.
All in One Mushroom Grow Bag for Multiple Flushes
Everything in one bag. Skip the tub, fruit directly.
HB4 Worm Based High Performance Substrate
Our worm-casting substrate. Layer it with your colonized grain.
Common Questions
Before you buy.
How do I inoculate the grain bag?
Wipe the injection port with 70% isopropyl alcohol. Inject 3-5cc of spore solution or liquid culture through the self-healing port. No need to open the bag. Store at 72-78F in a dark area.
How long until full colonization?
3-6 weeks depending on species, temperature, and culture health. You'll see visible mycelium within 5-10 days of inoculation. Once 30% colonized, break and shake to speed things up.
When should I break and shake?
When you see about 30% of the grain covered in white mycelium. Break up the clumps and shake the bag to redistribute. This spreads mycelium to uncolonized grain and can cut colonization time significantly.
What substrate should I pair this with?
Our HB4 substrate is designed to pair with this grain. One bag of MGM (4 lbs) pairs with one 5lb bag of HB4. Layer it spawn-to-bulk in a monotub at a 1:1 to 1:2 ratio.
Can I use liquid culture instead of spores?
Yes. Liquid culture colonizes faster than spores because the mycelium is already growing. Inject 3-5cc the same way. Many experienced growers prefer LC for speed and consistency.
How do I know if the grain is contaminated?
Healthy mycelium is bright white and rhizomorphic (ropy strands). Watch for green, black, or orange discoloration, sour smells, or wet/slimy spots. If your grain shows contamination before inoculation, contact us for a free replacement.
What Growers Say
Hear it from the grow room.
4.8 average across 19 reviews
★★★★★
"Fastest colonizing grain I've used. Had visible growth in 6 days. The millet really does make a difference compared to straight rye."Tyler R. Verified Grower
★★★★★
"Clean grain, perfect moisture. Inoculated 4 bags from one LC syringe and all 4 colonized without a single contam. That's a first for me."Dana K. Verified Grower
★★★★★
"Been buying grain from three different vendors. MMP is the only one where I haven't lost a bag to wet rot. Hydration is actually dialed."Pete S. Verified Grower
★★★★☆
"Good grain, good price. Paired with HB4 substrate in a 6qt monotub and pulled almost 2oz dry on the first flush. Ordering the 6-pack next."Morgan L. Verified Grower
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