Collection: Sterilised Mushroom Substrate Bags UK

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.

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.

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.

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.

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.

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.