GEM® came about as a result of the University of California Riverside’s avocado-breeding programme. A particularly promising batch of avocado seedlings, called ‘3-29-5’, was selected from a Ventura County test orchard by Dr Berthold O Bergh and Gray E Martin (initials GEM). The first 3-29-5 trees were top-worked in 1992 at UCR’s South Coast Research Centre. In 1995 3-29-5 material was imported into South Africa under a Non Propagation & Testing Agreement between UCR and Westfalia Technological Services (WTS). In 1999 the first 3-29-5 fruit was picked on a Westfalia farm.
In 2002, a US Plant patent application for 3-29-5 was filed, and in 2003 an application was filed for South African Plant Breeders Rights. PBR filing in other countries followed. A trademark GEM® was subsequently registered to be used for fruit of the cultivar that meet certain quality criteria.
In 2006 the University of California appointed WTS under an exclusive licence to develop the cultivar in sub-Saharan Africa.
In 2011, the University of California signed an exclusive licence agreement with Westfalia Fruit Estates to develop and market 3-29-5 internationally. Westfalia was appointed as the primary licensee for GEM® around the world.