The previous manager, Siew Gek Sim, left in June, after working at the garden for about a year and a-half.
Since then, the garden's four staff, and volunteers, had been running the facility.
Last year, the council reported the garden had more than doubled its expected income, taking $122,000 in its first 53 days of operation.
But Dunedin City Council community life general manager Graeme Hall said those numbers, which translated to about 8000 a month, had dropped to 3600 last month, and between 2500 and 2700 in the three months before.
Ms Winchester will begin work in January, and has moved from human resources work for Arrow International, with part of that work related to the Forsyth Barr Stadium.
Ms Winchester (39) said she had a postgraduate degree in tourism from the University of Otago, a background in hospitality, education, and business, and experience overseas before she returned to Dunedin about 10 years ago.
She said the garden needed to be marketed as a tourist attraction.
"When it first started it had a honeymoon period, and we need to keep that momentum up."
Her job would involve developing relationships with the community and tourism operators, and success would mean meeting visitor number targets, and turning the garden into a well-known tourism facility, on par with the likes of Larnach Castle.
Mr Hall said the council was looking forward to Ms Winchester improving the visitor experience at the garden, and following up national and international marketing opportunities to make the facility a standout feature for the city.
It was hoped more events could be held at the garden for those with a 12-month pass.
There were also plans for events at New Year, and the Chinese New Year, which next year falls on February 14, which is also Valentine's Day.
