The historic Ballarat Botanical Gardens have been heritage listed.

Heritage Victoria has added the 40-hectare site next to Lake Wendouree to the Victorian Heritage Register.

The gardens, developed from 1858, have significant mature trees, especially conifers and deciduous trees, which are some of the largest and most rare in Victoria.

Ballarat City Council sustainability executive manager Ian Rossiter said the listing would ensure that council's future management would honour and respect the gardens' style.

''It's a place of heritage significance because the gardens were established right at the city's settlement. This is quite remarkable,'' Mr Rossiter said.

The gardens is also of historical significance for the association with Baron Ferdinand von Mueller who supplied initial plant materials from the Melbourne Botanic Gardens.

The botanical gardens is home to the Australian Ex-Prisoner of War Memorial to honour 37,000 soldiers, the Ballarat Fish Acclimatisation Society's trout hatchery, wetlands, Ballarat Vintage Tramway Museum and the annual Begonia Festival.

The gardens have characteristics typical of the 19th century ''gardenesque'' style, including path layout, open lawn areas planted with mature specimen trees, formal avenues, bedding displays and horticultural buildings.

Heritage Council of Victoria chairman Daryl Jackson said a number of donations provided a collection of features, including statues and the Prime Ministers' Walk, which made the gardens the centrepiece of local civic pride.