Episode 171: Heavy Metals & Living Soil: How to Pass Compliance Testing with Greg Larson

Navigating tight heavy metal regulations while maintaining an organic living soil program isn’t easy—especially in states like South Dakota, Minnesota, and Maine.

In this episode of the Cannabis Cultivation and Science Podcast, host Tad Hussey sits down with commercial cannabis consultant Greg Larson to discuss:

• Targeted Lab Testing: Identifying heavy metal culprits across fertilizers, soil, and cultivation tools.

• Input Selection: Why land-based inputs outperform ocean-based ones for heavy metal safety.

• Biomass Removal: How pulling root masses removes accumulated arsenic over successive cycles.

• Soil Chemistry & Fertility: Maintaining optimal pH and phosphorus levels to prevent arsenic uptake through shared plant pathways.

• Beds vs. Containers: Why larger soil volumes lower heavy metal risks and drastically reduce labor costs.

Stream the full episode on your favorite podcast platform or watch on YouTube. You can reach Greg directly at: Gregory.d.larson@gmail.com