Collection: Substrates

Ready-to-use sterile substrate bags for mushroom cultivation. Available in CVG and Master Mix blends, perfect for gourmet, exotic, and functional mushroom species. Simply add colonised grain spawn and start growing. Produced in small batches, sterilised for 90+ minutes in our medical-grade autoclave, and delivered UK-wide with next-day delivery.

  • Add Mushroom Spawn

  • Watch Mycelium Grow

  • Set Fruiting Conditions

  • Harvest Your Mushrooms!

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Sterile Substrate FAQs:

What is a sterile substrate bag?

A sterile substrate bag is a pre-prepared mixture of mycelium supporting materials such as CVG (coco coir, vermiculite, gypsum) or Masters Mix that has been placed into a bag and sterilised to eliminate contaminants. The bag is sealed and ready for inoculation with colonised grain spawn.

Which substrate blend is best for mushroom cultivation?

CVG substrate is commonly chosen for gourmet and exotic mushrooms, while Masters Mix (hardwood fuel pellets and soy hulls) is favoured for higher yields in many gourmet species. The best blend depends on the mushroom variety and your growing goals.

How long will my sterile substrate bag last?

When stored in a cool, dark place, unopened sterile substrate bags generally last 2–3 months. For best results, use them as soon as possible after delivery.

How are your mushroom substrates sterilised?

We sterilise our mushroom substrate bags in our medical autoclave for 1 hour and 30 minutes, to ensure heat reaches the centre of each block. We then seal each bag in front of a laminar flow hood in our clean room, so no contaminants can get in.

Do you offer wholesale mushroom substrates?

Yes! We automatically apply discounts on up to 200 bags. But, if you're after a custom order, or wholesale mushroom substrates, you can contact us directly for a quote.

Do sterile substrate bags include mushroom spawn?

No, sterile substrate bags do not include grain spawn or mushroom genetics. They are supplied culture-free, so that you can add your own colonised grain spawn.

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