Collection: Sterile Grain

Our ready-to-inoculate sterile grain bags are designed for reliable mushroom spawn production. Each bag is made fresh in small batches and sterilised for 150 minutes in our medical-grade autoclave, ensuring a clean foundation for your liquid culture. Available in a range of grains, including rye and millet, they are trusted by both first-time cultivators and experienced mycologists. Delivered UK-wide with next-day delivery.

  • illustration of a mushroom grow bag being injected with a spore syringe

    Inoculate Your Grain Bag

  • Place Grains In Incubation

  • Leave Mycelium To Grow

  • Add Grain To Substrate

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Sterile Grain Bag FAQs:

What is a sterile grain bag?

A sterile grain bag is a ready-to-inoculate bag of grains (e.g., rye or millet) that has been sterilised to remove contaminants. It’s designed to be colonised with your chosen mushroom culture to create spawn that can be transferred to substrate

Which sterile grain bag should I choose?

Rye is a versatile, widely used grain for many gourmet and exotic mushroom species. Grains like millet and milo have smaller kernels, giving more inoculation points and often faster colonisation. We recommend choosing based on your strain’s growth behaviour, your preferred workflow, and the substrate you plan to use, for example, rye pairs particularly well with Masters Mix.

How do I use a sterile grain bag?

To use your sterile grain bag, just inoculate it via the injection port with a spore syringe or liquid culture, then let it grow! Once mycelium has fully colonised the bag of grain, you can safely call it grain spawn. Read more about using your sterile grain.

How long will my sterile grain bag last?

Unused bags typically keep up to 3 months when stored cool, dry, and out of direct light. For best results though, inoculate your grain bag as soon as possible after delivery.

How are your grain bags sterilised?

We sterilise all our grains in bags inside our medical grade autoclave for 2 hours and 30 minutes, with a pressure of at least 15 PSI and a temperature of 121ºC. Then, we seal the bags in front of a laminar flow hood in our clean room to minimise contamination risk.

Do you offer wholesale sterile grain bags?

Yes! We automatically apply discounts on bulk orders of up to 200 sterile grain bags. If you're after a customer order or want a wholesale quote for sterile grain bags, then just contact us directly.

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