Here are a few links to a variety of botanic gardens across New Zealand.

Auckland : Botanic Gardens

Christchurch : Botanic Gardens

Dunedin : Botanic Gardens

Wellington : Botanic Gardens

These gardens below are also worth a visit

Gardens to Visit 

Hamilton gardens

Oamaru Gardens

New Plymouth: Pukekura Park

Botanic Gardens of Australia & New Zealand 

Pictures of NZ Botanic Gardens = https://www.google.com.au/?gws_rd=ssl...