A new federally funded study has found that the chemical makeup of soil can significantly influence the bioactive compounds in cannabis, suggesting that farmers may be able to fine-tune cannabinoid and terpene production through soil management—not just plant genetics.
Published in the Journal of Medicinally Active Plants, the research shows that “poor soil quality appears to result in higher levels of THC production, whereas higher soil quality may result in higher levels of the precursor cannabinoid, CBG.” The findings could have major implications for outdoor hemp and cannabis cultivation as growers seek to balance potency, therapeutic properties and compliance with legal THC limits.
The study was supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture, Penn State College of Medicine and medical marijuana company PA Options for Wellness. Researchers compared two hemp cultivars—Tangerine and CBD Stem Cell—grown side-by-side in conventional tilled soil and in no-till fields with cover crops.
Significant differences emerged between the growing environments. The Tangerine plants cultivated in conventional fields produced about 1.5 times more cannabidiol (CBD) than those grown with cover crops, while the CBG Stem Cell variety showed the opposite trend—CBD levels doubled in the cover crop soil. Cannabigerol (CBG) levels were nearly four times higher in plants grown with cover crops, while THC concentrations were up to six times higher in the tilled field.
“Soil health or soil quality are often used interchangeably,” the authors wrote, “but soil health focuses not just on the inorganic properties of soil but also its biological properties and ability to promote life.”
Because soil hosts complex microbial and fungal ecosystems that influence nutrient uptake, the study suggests that improving soil biology could directly shape the cannabinoid and terpene profiles that define cannabis’s aroma and effects.
“This is the first study to show differences in extract composition of outdoor cultivated hemp grown in different soil conditions,” the paper notes, adding that further research is needed to understand the enzyme activity that drives cannabinoid synthesis.
Read the whole article from MarijuanaMoment here.
