The cannabinoid content of Cannabis sativa L grown in England

Abstract

Twelve varieties of Cannabis sativa were grown out-of-doors in southern England during 1971 to 1973. Results show that for certain varieties highly active herbal cannabis can be produced. A warm climate with abundant sunshine does not therefore seem to be essential for high THC content. This was supported by results of growing plants in a greenhouse in varying lighting conditions including a limited period in total darkness. Considerable within and between plant variation was found and the importance of defining the plant part used, the stage of growth and the size of the sample is emphasized for comparative work involving quantitative results. Comparison of the present results with those for the same cannabis varieties grown in different parts of the world shows that all exhibit the same qualitative picture, that is, either THC-rich or CBD-rich. Since this chemical composition seems independent of environmental conditions it is inappropriate to refer to the two types as phenotypes; it is more likely that they represent two chemical races within the species Cannabis sativa L.