Mushroom Substrate

Vermiculite for Mushroom Growing

Horticultural vermiculite for mixing CVG, making BRF cakes and holding moisture in your grows.

Available in 1, 2 and 4 litre bags
Lightweight, airy and water retentive
Key ingredient in CVG and PF Tek
Clean, sterile mineral
Also great as a dry layer on jars
Sterilised and sealed, ready to spawn
Guaranteed clean or we'll replace it free of charge

Size

Clear

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Lab preparedHEPA flow hood

DiscreetPlain packaging

Fast dispatchNext working day

Description
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Why Vermiculite?

Vermiculite is a natural mineral that has been heated until it expands into light, spongy flakes. It holds a lot of water while keeping substrate open and airy, which is exactly what mushroom mycelium likes. It is a core ingredient in CVG substrate and in brown rice flour cakes, and it is one of those things every grower ends up keeping a bag of.

What Is Included

1 x bag of vermiculite (1, 2 or 4 litres)

Common Uses

CVG substrate: mix with coco coir and gypsum for the classic bulk substrate.
BRF cakes: combine with organic brown rice flour and water in jars.
Dry vermiculite layer: a thin layer on top of jars acts as a contamination barrier.
Humidity: a damp layer in a fruiting chamber helps keep the air moist.

How Much Do I Need?

For a standard CVG mix, use roughly equal volumes of expanded coir and vermiculite. A 4 litre bag is a good size for one or two monotubs.

Our Tip

Medium grade vermiculite is the sweet spot for mushrooms. Very fine grades compact and very coarse grades do not hold moisture as well. We have used this grade for years with great results.

See our perlite, gypsum and brown rice flour, or skip the prep entirely with sterilised CVG. For bulk growing setups, browse mushroom spawn & substrate.