500gram Gypsum Powder Calcium Sulphate for Mushroom Substrate Grain Spawn
Our 500g Fine Gypsum Powder (Calcium Sulphate Dihydrate) is a must-have supplement for serious mushroom growers. Used during grain prep and substrate mixing, gypsum helps improve nutrient availability, pH stability, and moisture retention, leading to faster colonisation and more robust fruiting.
Ideal for mixing into grain spawn (e.g., rye, millet) and bulk substrates like CVG (coco coir, vermiculite, gypsum), it prevents clumping, enhances texture, and provides essential calcium and sulphur for optimal mycelium health.
✅ Pure food-grade Calcium Sulphate Dihydrate
✅ Prevents grain clumping & improves colonisation
✅ Enhances substrate structure and water retention
✅ Essential for preparing CVG or Masters Mix
✅ Supplied in resealable packaging for easy use
Specifications:
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Weight: 500 grams
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Type: Calcium Sulphate Dihydrate (Gypsum Powder)
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Grade: Food-grade, ultra-fine powder
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Use Rate: ~5–10% by weight in substrate/grain mixes
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Storage: Cool, dry place in sealed bag
Details
Each product is freshly prepared using high-quality, lab-grade materials and sterilised using professional pressure sterilisation techniques.
Shipping & Returns
Due to the sterile nature of our products, returns are not accepted. However, if your item arrives damaged, contaminated, or incorrect, contact us within 48 hours of delivery with photos and we’ll resolve the issue.
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