"People think 'oh that's cute, but is it really city building?'
"Yes, it is city building! Not only does it make people smile, but the fact is, people don't yarn bomb something they don't care about."
Taking the time to knit a sweater for a tree showed people had an emotional connection with their city.
Speaking at Tauranga Boys' College last night, one of several stops on Mr Kageyama's weekend visit to Tauranga, he gave examples of small "and sometimes silly" city building and encouraged citizens to go out and make their city better themselves.
Mr Kageyama visited Tauranga in 2013 and said it was interesting to see things that were only just getting started three years ago had "fully blossomed".
"The Hairy Maclary statue is brilliant."
The statue was playful and invited people to interact with it, either kids playing on it or taking photos, he said.
"That is the best of public art right there. Too many people think public art should be this highbrow stuff, but frankly that's what museums are for.
"Public art is for citizens and to make people smile and feel good about the places they are in and Hairy Maclary does that exceptionally well," Mr Kageyama said.
As for Tauranga's proposed plans for a new civic heart, Mr Kageyama applauded the notion and the effort.
"It's a once in a generation opportunity to remake the central iconic buildings in your downtown."
Though there were varying opinions about what should go where he said it would be a huge step forward for Tauranga.
He particularly mentioned the plans for pedestrian only zones, green spaces and public plazas where people could naturally gather.
Mr Kageyama was in Tauranga for a three-day visit, talking to city business leaders, the Tauranga City Council's community development team and the rotary club.
Next stop in his New Zealand trip was Dunedin, where he was the keynote speaker at a local government conference.