Description

Bulk Sterilised Millet Mushroom Grain Spawn Bag – 25–1000 Unit Packs

Scale up your spawn production with lab-prepped millet & milo grain that’s ready to inoculate. Built for growers who care about consistent colonisation, clean results, and a supply they can actually rely on.

Each bulk grain spawn bag is prepared in cleanroom conditions and sterilised in a computer-controlled autoclave, taking the guesswork out of prep so you can focus on growing, not fixing problems.

Choose 1kg or 1.5kg bags in 25, 50, 100, 250, 500 or 1000 unit packs for commercial consistency and better unit economics.

Need trade support, custom scheduling, or a tailored quote? Contact us and we’ll build a supply plan around your volume.

Wholesale‑Ready Sterilised Grain Blend

This is our best-selling sterilised millet + milo (milo = sorghum) grain blend, optimally hydrated and sealed in an injection-port bag - designed as a fast, contamination-resistant foundation for grain spawn production.

Ideal for

• Commercial farms and scaling growers who rely on consistent cycle times and repeatable results
• High-volume hobby growers who want access to wholesale pricing without complicated sourcing
• Retailers and resellers looking for a reliable, high-performing sterile grain range

Not a Bulk Buyer?

This page is for trade, wholesale, and high‑volume growers ordering 25–1000+ units.

If you’re a hobby grower or want to trial smaller quantities first, use our standard (non‑bulk) listing here.

Key Advantages

• Direct from the source - You get the best price. It's all about direct supply from a top UK mushroom supplier.
• Scale whenever you’re ready - Need 25 now or 1,000+ regularly? We’ve got you covered year-round.
• Rapid colonisation - Smaller millet grains mean mycelium finds more spots to grow, letting it cover the substrate faster than larger grains.
• Clean, commercial-grade sterility - Each batch is sterilised for 2.5 hours at 121°C in a computer-controlled autoclave at our Kent facility, giving you a contamination-free start.
• Perfectly balanced moisture - Grain is hydrated just right to encourage healthy, vigorous growth without inviting bacteria.
• High-quality filtration - 0.2-micron filter patches let the bags breathe while helping keep contaminants out - so you get more consistent results.
• Self-healing injection ports - Make inoculation straightforward, whether you’re using spores or liquid culture.

What You Get

• Bulk packs 25–1000 to match your production runs
• Two bag weights: 1kg or 1.5kg to fit different SOPs
• Optimally hydrated millet & milo blend for rapid colonisation
• Cleanroom-prepped and ready to inoculate on arrival
• Sterilised in a computer-controlled autoclave (2.5 hrs @ 121°C)
• Lifetime Guarantee (we stand behind every bag)
• Free UK delivery on £50+ orders helps protect margins
• Pay in 3 interest-free instalments available at checkout

Built For

Product Sellers (retailers, resellers, garden centres)

• Building a sterile grain line with repeatable quality
• Offering case quantities for serious growers
• Improving customer outcomes with a proven grain blend and guarantee

Growers (commercial & high-volume)

• Routine inoculation runs with consistent, clean grain
• Grain-to-bulk workflows (monotubs and blocks)
• Faster SOPs: no soaking/cooking/sterilising on your end

Perfect For

• Spawning to bulk with CVG-style substrates for tub grows
• Wood-based fruiting blocks when paired with hardwood substrate mixes
• Cycle consistency when you need predictable colonisation windows (typically 3–4 weeks, culture-dependent)

What’s Included

• 1kg or 1.5kg sterilised millet & milo grain bag (per unit)
• Lifetime Guarantee coverage

Not included: spore or liquid culture syringe.

How It Works

1. Sanitise your workspace and wipe the injection area on the bag.
2. Inject your spores or culture through the self-healing port.
3. Incubate until colonised (often 3–4 weeks, depending on culture and conditions).
4. Spawn to bulk:

• • For “therapeutic/functional” style grows: 2:1 bulk substrate : spawn
  • For gourmet mushrooms on wood substrate: 6:1 wood substrate : spawn

Quality Guarantee

At Martian Mushrooms, we don't just sell supplies; we use them.

Every batch is produced with lab-first discipline: grain is soaked/cooked, hydrated to ~50% water content, and sterilised in a computer-controlled steam autoclave for 2.5 hours at 121°C.

If something goes wrong, you’re protected by our Lifetime Guarantee - built for growers who can’t afford downtime.

Technical Specifications

Martian Mushrooms vs. Competitors

Don't let grain prep slow you down. Ensure your supply chain with the UK's most reliable bulk grain spawn.

Need a custom quote, white labelling, or pallet pricing (100+ units)?

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