UK Mushroom Growing Guides
Practical, no-nonsense guides for growing gourmet mushrooms at home in the UK. Written for beginners by people who actually run grows.
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Compare substrate, temperature, fresh-air and difficulty guidance for ten legal gourmet and functional species.
Browse mushroom strainsHow to Grow Mushrooms at Home in the UK: The Complete Beginner's Guide to Gourmet Cultivation
Learn how to grow mushrooms at home in the UK, from choosing a beginner kit to managing humidity, avoiding contamination and harvesting your first crop.
Best Mushroom Growing Kit in the UK (2026 Buyer's Guide)
Compare UK mushroom growing kits for beginners: cardboard box kits versus all-in-one grow bags, what to look for, what to avoid and realistic yields.
How to Grow Oyster Mushrooms at Home in the UK
Grow oyster mushrooms at home in the UK: substrate choices, spawn ratios, temperatures, fruiting conditions and realistic yields for pearl, blue and pink.
Agar, Liquid Culture & Spores: A Beginner's Guide to Clean Mushroom Cultures
A UK beginner guide to clean mushroom cultures: what spores, liquid culture and agar do, how to test a culture, clean-work setups, transfers and records.
Grain Spawn for Beginners: Choosing Grain, Hydration, Sterilisation & When It's Ready
A UK beginner guide to grain spawn: choosing millet, rye or wheat, hydration methods, sterilising, break and shake, and knowing when spawn is ready for bulk.
Mushroom Biological Efficiency Explained: How to Calculate BE %
What biological efficiency means in mushroom growing: the BE % formula, why dry substrate mass matters, worked examples and how to compare grows fairly.
Mushroom Spawn to Substrate Ratio: What 1:2, 1:3 and 1:4 Mean
What spawn to substrate ratios mean, how to work out spawn weight at 1:2, 1:3, 1:4 and 1:5 by mass, why conventions differ and the real trade-offs involved.
Mushroom Substrate Hydration: Water Content, Hydration Ratio and Field Capacity
How much water to add to mushroom substrate: the two hydration conventions, the mass-balance formula with worked examples, and why field capacity decides.
Mushroom Growing Equipment UK: What You Actually Need
A practical UK guide to mushroom growing equipment: what is essential for ready-to-fruit blocks, spawn and bulk substrate or full culture work, and what is not.
Mushroom Fruiting Air Exchange: CO2, CFM and Fresh Air Explained
Why fruiting mushrooms need fresh air, how to turn room volume into a CFM target, what the 5-10 minute exchange rule means, and why measured CO2 beats timers.
Mushroom Contamination Guide: Green Mould, Cobweb and Bacterial Blotch
A cautious UK guide to gourmet mushroom contamination: green mould, cobweb growth, bacterial blotch, wet substrate, and how to tell them from healthy mycelium.
Master's Mix Mushroom Substrate: 50:50 Hardwood & Soy Hulls Explained
A UK guide to Masters Mix: what 50:50 hardwood sawdust and soy hulls means, dry recipe versus hydrated block, a worked batch at 60% water, and sterilising.
How Much Grain Spawn per Kilogram of Substrate?
Quick lookup for how many grams of grain spawn to use per kilogram of bulk substrate at 1:2 to 1:5 ratios, with a batch table from 1 kg to 10 kg.
How to Calculate a Masters Mix Ratio: Hardwood, Soy Hulls and Water
The arithmetic behind a 50/50 hardwood-to-soy-hull Master's Mix by dry weight, plus how much water to add to hit a target moisture, with a worked batch example.
How Wet Should Mushroom Substrate Be? Field Capacity, the Squeeze Test and the Two Percentage Conventions
What field capacity means for mushroom substrate, how to use the squeeze test, and the tell-tale symptoms of over-hydrated and under-hydrated bulk substrate.
When to Break and Shake Grain Spawn (and When Not To)
How to tell when grain spawn is ready to break and shake, how to do it cleanly and safely, and why shaking too early or too often costs you colonisation time.
Liquid Culture vs Spores: Which Should You Start With?
Liquid culture or spores for gourmet mushroom growing? A comparison of speed, cost, consistency and contamination risk, with a decision table.
When Is Grain Spawn Ready for Bulk Substrate?
How to tell when grain spawn is fully colonised and ready for bulk substrate, what consolidation looks like, and what to do if a jar stalls.