Record Cannabis Yields Achieved With Precision Stone-Wool Growing Systems
Commercial cannabis trials at a Montreal research facility produced average dry flower yields of 9.7 kg/m², with peak results exceeding 10 kg/m², using optimized stone-wool substrates and F1 hybrid autoflower genetics.
A collaborative research trial between stone-wool substrate manufacturer Grodan, cannabis seed developer F1 SeedTech, and the CRIC Research Center in Montreal has produced what may be the highest documented commercial cannabis yields to date. The fifth trial in an ongoing series recorded average annual dry flower yields of 9.7 kg per square meter — equivalent to 1.98 pounds per square foot — with four of eight treatment groups surpassing the 10 kg/m² threshold across 5.7 crop turns per year.
The trial utilized F1 SeedTech's autoflower hybrid varieties Miss Beauty and Florence Fusion, grown in Grodan's 3.2-liter Hugo stone-wool blocks. Researchers tested two electrical conductivity levels — 3.2 mS/cm and 2.7 mS/cm — while progressively increasing irrigation shot sizes from 1% to 3% to 4.5% of substrate volume over a six-week flowering period. Real-time root-zone monitoring through Grodan's GroSens Suite enabled precise adjustments throughout each growth cycle.
The results highlight the critical role of substrate management in maximizing cannabis output. Stone-wool's inherent steerability allows cultivators to send targeted vegetative or generative signals during specific growth phases by manipulating EC levels and irrigation timing. This precision approach contrasts with common commercial practices where growers push EC levels three to four times higher than optimal, sacrificing balanced growth for perceived potency gains that ultimately reduce overall yields.
For commercial operators, the yield figures carry significant economic implications. Achieving nearly 10 kilograms of dry flower per square meter annually represents a substantial improvement over industry averages, which typically range from 3 to 5 kg/m² in well-managed indoor facilities. The combination of fast-cycling autoflower genetics and precision substrate management enables more crop turns per year while maintaining quality, directly improving facility throughput and per-square-foot revenue.
The research also demonstrated potential sustainability benefits beyond raw yield improvements. Optimized EC management and precision irrigation reduced drainage requirements, lowered fertilizer waste, and improved water and nutrient use efficiency. These operational savings compound with the yield increases to substantially improve gross margins for cannabis cultivators operating in competitive markets where cost control increasingly determines profitability.