We will not be taking orders until November 2019 due to business re-structuring. We apologise for the delays.

Gypsum (Calcium Sulphate)

4.50 out of 5
(4 customer reviews)


Gypsum is used at almost every stage of mushroom cultivation, adding essential minerals and trace elements to bulk substrates or grain, aiding in mushroom development and increasing yields.

Hand-Packed with ❤ in Bristol, UK.

Our powdered Gypsum can be added to soak or boil water at grain preparation stage or direct to substrate as a nutritional supplement. Is also commonly used to stabilise the PH of substrates, preventing wild swings. Gypsum has a natural PH of 7 (neutral).

  • Provides essential minerals & trace elements for healthy mycelium (mainly calcium and sulfur)
  • Promotes proper fruit-body formation
  • Increases yields during fruiting
  • PH Stabilisation of Substrates
  • Helps with grain separation after boil and prevents sticking and clumping, leading to larger mycelial mass and less chances of bacterial infection.
  • Allows for even and consistent moisture flow when added to bulk substrate
  • Suitable for any mushroom substrate
  • Pure Calcium Sulphate
  • Horticultural Grade

Can be added up to 5% of dry weight of substrate or grain, recommended 2-3%.


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Frequently Bought Together

BUILD YOUR OWN GEAR! - View our kit lists @ KIT.com

Fruiting Room Lab Substrate/Spawn Preparation
Must Have Books Order Preparation
  • Packaging & Scales
  • Mushroom Dehydrator Build

Tincture Production

Vlogging Equipment & Digital Production


4 reviews for Gypsum (Calcium Sulphate)

  1. 5 out of 5

    Andy V.

    Very beneficial to mushroom growth. Good product, fast free delivery, well packaged. Wide selection of products available. Thank you.

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  2. 5 out of 5


    Used extensively in almost all stages of mushroom production to give essential nutrients to mycelial growth. A safe nutritional supplement for beginners which has noticeable effects if compared to grows without. Good price when ordered in bulk. ~ Han

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  3. 4 out of 5

    Clairey Baby

    fast delivery. well packaged. good quality

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  4. 4 out of 5


    looks to be making a huge difference in my A/B tests growing oysters (as I was told it would following advice on other websites). Pretty cheap stuff considering the benefits it makes and free shipping. Top drawer.

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100g, 250g, 500g, 1kg, 2kg, 5kg

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