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.
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:
- Coco coir bricks or loose coco coir
- A large pot.
- A thermometer
- An old pillow case.
The first step is to hydrate the coco coir. If you are using coco coir bricks, you will need to break them up and soak them in water for at least an hour. If you are using loose coco coir, you can skip this step.
The amount of water you need depends on the amount of coco coir you have, but a general rule of thumb is to use twice as much water as coco coir by volume.
Next, you will need to measure out the vermiculite and gypsum and mix them together with the coco coir until you have a uniform substrate.
The next step is to pasteurize the substrate to kill any unwanted microorganisms that could compete with or contaminate your mushrooms. There are many different methods of pasteurization which you can read about on “how to pasteurize mushroom substrate”, choosing one which suits you best.
However, a quick and basic method follows:
- Place the substrate into an old pillow case or similar then tie it.
- Heat a large pot (I will use my pressure cooker) of water to around 165F (73c).
- Submerge the substrate in this water for around an hour ensuring the centre of the substrate is between 140f-170f (60°C – 76c).
- Remove the substrate from the pot and allow it to drain for an hour or two.
Correct hydration levels.
The final step is to check and adjust the hydration level of your substrate. You want your substrate to be at field capacity, which means it holds as much water as possible without dripping when squeezed. To test this, take a handful of substrate and squeeze it firmly. If no water comes out, it is too dry and you need to add more water. If water drips out easily, it is too wet and you need to drain some water or add more dry ingredients. If only a few drops come out, it is just right and ready to use.
I normally just correct my hydration while i'm spawning to bulk by grabbing a handful giving it a big squeeze until it is at field capacity.
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?