Grow mushrooms the EZ way.

Cococ Coir (CVG) Substrate Recipe.

Coco Vermiculite & Gypsum, commonly referred to as CVG, stands as a tried-and-true substrate blend in the mushroom cultivation world. This mixture is favoured for its excellent water retention, aeration, and nutrient content, making it ideal for a wide range of mushroom species.

CVG is easy to prepare and all the ingredients are widely available at horticultural stores.

I've used CVG a ton of times in King Oyster grows with great success, this substrate as is cheap and easy to prepare. 

Substrate Recipe.

A common recipe for CVG is: 

  • Coco Coir: 650 grams.
  • Vermiculite: 2 Litres / Quarts.
  • Gypsum: 240ml.

If you have a different sized coco coir brick use our CVG recipe calculator below:

CVG Recipe Calculator





To make CVG substrate, you will need the following supplies:

  1. Measure Your Ingredients:

    • Typically, a ratio of 650g Coco Coir, 2L vermiculite, 240ml Gypsum and 4.25l Water. Adjust quantities based on the size of your coir brick and the amount of substrate you need, using the calculator above.
  2. Prepare the Coco Coir and Vermiculite:

    • Place half the vermiculite and gypsum on the bottom of the bucket.
    • Place the coco coir on top.
    • Place the rest of the vermiculite and gypsum on top (this will mean it mixes better when hydrating).
    • Pour boiling water over the CVG mixutre and close the lid on the bucket.
    • Wrap the bucket in insulation wrap or towels to keep the tempreture higher for longer (this step is optional but i do it).
  3. Cool Down:

    • Leave overnight to pasteurize and the come back to it in the morning
  4. Add the Grain Spawn:

    • Once the substrate has cooled, add your grain spawn to the bucket.
    • Use gloves to maintain sterility and mix the spawn thoroughly with the substrate to ensure even colonization.
    • Move the bulk substrate into your fruiting vessel such as a monotub.

By following these steps and maintaining a clean working environment, you can successfully prepare a Bucket Tek CVG substrate for mushroom cultivation.

It is also possible to perform all these steps in the bag which the coco coir comes in as shown in the video above.

Why do we use CVG?

Overall this substrate gives enough hydration, nutrients and aeration to fruit mushrooms whilst not being over nutritious and inviting a high contamination risk.

  • Coco coir is a fibrous material derived from coconut husks. It has a high water-holding capacity, a neutral pH, and a good texture for mushroom growth.
  • Vermiculite is a mineral that helps to retain moisture, aerate the substrate, and buffer pH changes.
  • Gypsum is a calcium sulfate mineral that provides calcium and sulfur to the mushrooms, as well as improving the structure of the substrate.

Which Gourmet mushrooms can CVG be used for?

King Oysters.


Freckled Chestnut.

Lions Mane.


Coco Coir (CVG) Mushroom Substrate Recipe