A Giant Thistle ?

Today is our last day in New Zealand - still very hot and beautiful blue skies here in Dunedin. We both decided we would like to slow the pace a bit and so a leasurely walk along the Water of Leith ( suggested by marchmont) and we found ourselves at one of the entrances to the Botanic Gardens.
This proved to be delightful as there were many colourful flowering plants and shelter under some magnificent trees.
As a wee bonus we found ourselves in the midst of an annual event " Lark in the Park " with crowds of families enjoying entertainment, music and dancing of many types by the children and picnics on the grass.
I am not very good on plants ( better on animals!) so I have no idea if this plant which must have been at least 8 feet tall with a very thick stem is a type of thistle or not - certainly dwarfs our national emblem!
Extra is a view of the Water of Leith - but not the one in Edinburgh!