How We Test Mushroom Grow Kits

Every kit we review goes through the same rigorous process. No shortcuts, no special treatment. Here's exactly how we do it.

Step 1: Purchasing

We buy every kit ourselves, at full retail price, from the supplier's own website or a major UK retailer. We never accept free samples or discounted kits. This means we experience the exact same purchasing process you would. including delivery times, packaging quality, and any issues with the order.

We keep all receipts and document the purchase date, delivery date, and condition on arrival. If a kit arrives damaged or with obvious issues, we note that in the review but still attempt to grow it.

Step 2: Unboxing & First Impressions

We photograph everything as it comes out of the box. We assess the quality of the packaging, the clarity of the included instructions, and the overall presentation. We check the substrate for signs of contamination, proper colonisation, and moisture levels.

The instructions get a particularly close look. A kit aimed at beginners should have clear, step-by-step directions with photographs. We follow the instructions exactly as written. if they tell us to soak the block for 12 hours, we soak it for 12 hours.

Step 3: Growing Conditions

All kits are grown in the same spare bedroom in our house. We maintain consistent conditions:

• Temperature: 18-22°C (we adjust for species that need cooler or warmer conditions, as per the kit instructions)
• Humidity: 80-90% relative humidity, maintained with a small humidifier and measured with a digital hygrometer
• Light: Indirect natural light from a north-facing window, supplemented with a standard LED desk lamp on a 12/12 cycle
• Air circulation: Room ventilated twice daily for 10 minutes
• Misting: 2-3 times daily with filtered water at room temperature

Step 4: Daily Observations

From the moment we start growing, we take daily photographs and notes. We record:

• Day of first visible pinning
• Growth rate and appearance
• Any signs of contamination or stalling
• Temperature and humidity readings (twice daily)
• Any deviations from expected growth patterns

Step 5: Harvest & Measurement

Each flush is harvested when the mushrooms reach optimal maturity (just before or as the caps begin to flatten, depending on species). We weigh every harvest on a calibrated kitchen scale accurate to 1 gram. We record:

• Fresh weight of each flush in grams
• Number of individual fruiting bodies
• Visual quality and size consistency
• Time between flushes
• Total yield across all flushes

Step 6: Scoring

Every kit is scored out of 10 across six equally weighted categories. The final score is the average of all six:

Retesting Policy

If a kit scores poorly and the manufacturer contacts us to say we received a faulty batch, we'll purchase a second kit and retest. The review will show both results. We also periodically retest popular kits to check for consistency across batches.

Editorial Independence

We do not accept payment, free products, or any other consideration in exchange for reviews. Where we include affiliate links, these are added after the review is written and have zero influence on our scoring or verdicts. Our opinions are our own, based entirely on what happened when we grew the kit.

Questions about our process? Get in touch. See our latest reviews on the reviews page.