In Hastings, the police had found more than 200 nearly-mature cannabis plants at a leased commercial property on Orchard Road.
It was estimated the plants had a street value of between $600,000 and $750,000.
Three different rooms in the building were used for growing, with 72 plants in each room, at different stages of growth.
There was also evidence at the property to suggest the growers were stealing electricity to power lights and fans to aid the growing process.
Two men - aged 45 and 49 - were charged with cannabis cultivation and would appear in Hastings District Court on Friday.
Detective Inspector Marty James said it was a significant, large-scale commercial operation.
"It is one of the biggest cannabis growing operations I've seen in Hawke's Bay, with 216 well-propogated plants just coming into production."
James said there would have been a significant cost involved in setting up the operation.
"I believe we busted the operation right before the growers were able to harvest their first crop."
The property had only been leased three months ago.
He said it was a valuable reminder to commercial property owners to do their due diligence when leasing properties to tenants.
"Be mindful about who your tenants are, and what they are actually doing in your buildings."
