G-13 is a strain of legend and rumor said to have been bred in the 1970s in a US government research facility located at the University of Mississippi. The 100% indica strain was the best of a series of Afghani strains cultivated in the lab that were labeled G-1 through G-23. A female clone of the G-13 strain was liberated by one of the facility's research assistances, or so the story goes, and it spread throughout underground marijuana gardens in the US and Europe - eventually making it to Holland in the 1980s where breeder Neville Schoenmaker famously crossed G-13 with Haze.
Pure G-13 does not exist today but it lives on in hybrid strains
A pure G-13 marijuana strain is not known to exist today, however many popular crosses can be found that date back to Schoenmaker's work in the 1980s.
Mr. Nice, which is G-13 x Hash Plant, is considered the closest descendant of G-13 available today. Originally released as a limited edition strain from Sensi Seeds in the 1990s, G-13 x Hash Plant was later put back into production by Sensi Seeds in 1999 under the name Mr. Nice.
Soma has crossed 11 different G-13 hybrids
Famed breeder Soma managed to grow a male G-13 x Haze plant from some seeds he received from Schoenmaker around 1988. With that male G-13 x Haze plant, Soma has crossed eleven different hybrids, many of which are available from Soma Seeds today. Soma considers these strains some of his best work and they represent some of the closest remnants of G-13 available.
G-13 Marijuana Strain Reviewed by 91LIFE on February 11, 2013 in Los Angeles, CA