Interest in CBD is growing fast, with an increasing body of credible scientific research pointing to this cannabinoid's numerous medicinal properties. This post is intended to clear up some questions about CBD in traditional 'drug' strains.
If you are looking for CBD-rich traditional cannabis plants then you are best to look at charas and hashish strains (or at fibre hemp strains, but RSC has only once sold a fibre hemp strain from Northern Laos).
Hashish strains from the Himalaya, Middle East, and Hindu Kush such as the Parvati, Mazar-i-Sharif, and Lebanese can be expected to show CBD in roughly 75% of plants.
Evidence suggests that there are three basic 'chemotypes' which will show in traditional hashish landrace crop:
1. Type 1 plants: high THC, low CBD
2. Type 2 plants: roughly equal amounts of THC and CBD
3. Type 3 plants: high CBD, low THC plants
Type 2 plants can be expected to make up about half of any crop, and Type 3 plants about a quarter. Note that 'high' and 'low' are best considered as ratios: some plants will have high overall cannabinoid content, some low.
Unlike hashish and charas plants, most tropical ganja strains don't contain medically useful amounts of CBD. So that rules out varieties like Kerala, Thai, and Highland Lao. The reason for that is that ganja strains have had generations of selection for maximum potency (i.e. THC) and this has effectively bred the genes for CBD out (CBD is not psychoactive, contrary to the old urban myths).
A strain with good amounts of CBD tends to produce a more centred, clear, and grounded experience than high THC varieties do. For many people, this gives a more enjoyable and indulgent high. Notably, the Lebanese has shown some promising high-CBD plants, one of which is pictured below.