How To Fold Mushroom Grow Bags

Folding Mushroom Grow bags for sterilisation

What Are Mushroom Grow Bags

Mushroom grow bags are special bags made from a plastic which can withstand the extreme conditions within a pressure cooker. Mushroom grow bags are primarily used for the sterilisation of media for the production of grain spawn and heavily supplemented bulk substrates.

Why Use Mushroom Grow Bags?

Mushroom grow bags are used to sterilise media in the production of grain spawn or bulk substrates with a high level of supplementation like masters’ mix.

These filter patch bags allow for fresh air exchange during colonisation while ensuring that the contents remain free from contamination.

When correctly folded and loaded filter patch bags will self seal during the sterilisation process reducing the likelihood of contamination. 

How To Fold A Mushroom Grow Bag

Mushroom grow bags need to be folded for loading into the pressure canner, cooker or autoclave for sterilisation. We use 2 different types of fold however the second style of fold is optional. 

Fold Type A is used for bags that sit partly submerged in water during the sterilisation process. Fold Type B is used on bags that sit above water level during sterilisation. 

There are many different methods that can be used with folding and sterilising grow bags. The method described in the article is what works best for us.

Fold Type A

Fold Type A can be used on bags that either sit submerged in water or above water level during sterilisation.

Flatten the opening of the bag down along the gusseted edges. Apply pressure and dispel excess air from within the bag. The mouth of the bag should align perfectly. Take the flattened mouth and continue to wrap around the bag.

Sit the block with the filter patch facing upwards. Take the flattened mouth of the bag and fold back over the filter patch. Use 2 pieces of masking tape to adhere each side of this newly created concertina fold to the block.

Type a mushroom grow bag fold
Fold Type A - The tail of the bag is folded back over the filter patch.
Type a mushroom grow bag fold
Fold Type A - The concertina fold is held down on both sides with tape.
Type b mushroom grow bag fold
Fold Type B - The tail of the bag is wrapped around and taped down.

Fold Type B

Fold Type B can be used on bags that either sit submerged in water or above water level during sterilisation.

Flatten the opening of the bag down along the gusseted edges. Apply pressure and dispel excess air from within the bag. The mouth of the bag should align perfectly. Take the flattened mouth and continue to wrap around the bag.

Use a piece of tape to adhere the flattened mouth part to the black.

Prevent Burst Grow Bags

Learn how we load our pressure canner to avoid burst, broken & melted mushroom grow bags.

View Our Series Of Grow Guides

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