Study: Soil Types Can Alter Cannabinoid Concentration 

A study published last month in the Journal of Medicinally Active Plants suggests that the type of soil hemp is cultivated in can significantly alter cannabinoid concentration. The researchers, from the Penn State College of Medicine, Penn State plant biology program, and Keystone State Testing Laboratory, compared hemp grown in conventionally tilled fields to hemp grown using no-till cover crop methods and found that the hemp grown in conventional soil produced THC levels up to six times higher than plants grown in cover crop fields.    

“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.” — Impact of Soil Quality on Cannabinoid and Terpenoid Content of Cannabis sativa L, Journal of Medicinally Active Plants, 11/30/2025 

The researchers also found CBD levels 1.5 times higher in Tangerine cultivars cultivated in conventionally tilled fields and two times higher in cover crop no-tillage fields. CBDA levels were 6.3 times higher in Tangerine cover crop grown extracts and 2.2 times higher in conventional field-tilled extracts of CBG Stem Cell. CBG levels were 3.7 times higher in CBG Stem Cell extracts from no-tillage grown plants, while THC levels were 6 times higher for conventional tillage field grown Tangerine extracts.   

“Differences in terpene composition were observed between the cultivars grown in the [conventional tillage fields],” the authors note, “but not between those grown in [cover crop no tillage fields.]”  

The authors add that the study is the first “to show differences in extract composition of outdoor cultivated hemp grown in different soil conditions.” 

The research was funded by the U.S. Department of Agriculture National Institute of Food and Agriculture and medical cannabis company PA Options for Wellness.