Police in Auckland said their month-long operation netted 10 tonnes of cannabis and shut down 120 grow houses.
They said it was so much cannabis that four trucks a week were needed to take it away in the Waitematā district alone.
Officers say the plants were largely hidden in plain sight in average-looking rental properties in areas like Pōkeno in the south, Pakuranga in the east, Henderson in the west and Torbay to the north.
More than half a tonne of cannabis was located by Auckland City Police at a warehouse in the Penrose area.
Further south, Counties Manukau Police destroyed more than 140 kilograms of cannabis and 4200 plants.
Police say most of the people arrested were from Vietnam and going through deportation at the time.
They say cannabis grow houses linked to Vietnamese organised crrime are increasingly coming to their attention.
"Police efforts have dealt a significant blow to the pockets of organised crime figures and their associates, denying them a payday of more than $50 million," McNeill said.
He said growing cannabis was not the only illegal activity taking place on the properties.
"We know these rental properties are often fitted out with shoddy electrical wiring, fuelled by stolen power which is diverted from other properties.
"It's not only illegal but poses very real dangers to those operating the grow houses and innocent members of the community."
In many instances police have been called to residential house fires after evidence of a cannabis grow operation was discovered, he said.
McNeill said in many cases private landlords weren't carrying out basic checks before or during tenancies.
"If tenants move in and turn your house into a growing operation, you risk being liable in the event of a fire or significant damage."
He said landords should do reference checks, meet tenants face-to-face and check IDs, carry out credit and income verifications and regularly inspect their properties.
Police say the operation has taken $58 million out of organised crime.
