Curator of plants and gardens Kevin Frediani said staff had always passed on knowledge over a protracted period to new recruits, "with some risk of mistakes".
He added: "This experiential learning has been the norm in zoos and has proved very successful, albeit very time consuming."
Paignton now has a trainee gardener position that will run for two years, replacing a retired part-time gardener. The zoo offered the post to someone local. It includes being enrolled with Cannington College, which has a campus at the zoo.
It now offers an outreach service that has enabled the zoo to put its trainee on a two-year part-time NVQ Level 2 in amenity horticulture.
Frediani said: "The obvious difference being they have specialist knowledge in zoological horticulture, which is one of the growing sectors in the heritage and botanic gardens but has to date not had a specialist route into it for the young untrained gardener."
In addition to the traineeship, a new course in zoological horticulture was launched with Bridgewater College last week.
Up to 12 students will be enrolled on a year-long course from September, based in the Cannington campus at the zoo.