JAILED: Michael Quinlan, owner of the Switched On Gardener chain of hydroponic stores.

The owner of the Switched On Gardener chain of hydroponic stores has been sentenced to four years and three months in prison.

Judge Andree Wiltens refused the option of home detention as he sentenced Michael Quinlan in the Auckland District Court today.

General manager Peter Bennett, 43, was also sentenced, receiving a prison term of three years and nine months.

Two women broke down in tears as the sentence was read out to the packed courtroom.

The men were found guilty in December of supplying equipment for cultivating cannabis, but both were acquitted of being part of an organised criminal group.

Stoneware 91, the trading name for Switched on Gardener, and Hydroponic Wholesalers were fined $125,000 each.

Judge Wiltens said Switched on Gardener operated "close to the edge" as a significant proportion of its business activity was cannabis-related.

"What was going on was prevalent but also well known by everyone."

Staff were known to smoke cannabis at work stocktakes, the car number plate read "Bud1" and the company brand was a leaf, he said.

"While on its own this is not illegal, putting that facts together, with the way the company conducted its business, it simply added to the companies' overall picture."

The judge said Quinlan was culpable, whether he was aware of the criminal activity or simply turned a blind eye to it.

"There was an obligation on you. You had a responsibility because of your position. You had a ability to do something about it, but you failed to do it."

He dismissed the defence's argument that Bennett was unaware of the criminal activity.

"The suggestion he didn't know what was happening beggars belief," he said.

Police raided Switched on Gardener stores in April 2010, arresting more than 250 people connected to the case.

Stores in Auckland, Tauranga, Hamilton, Taupo, Hastings, Upper Hutt, Wellington, Nelson, Christchurch and Dunedin were included in the indictment.

It followed an undercover operation targeting the stores, which sold hydroponic growing equipment, fertilisers made for cannabis with names like "Budzilla", and marijuana pipes.

Posing as entrepreneurs, undercover police officers bought equipment from the stores and expressed interest in setting up a similar store using supplies from Quinlan's companies, the trial heard.

Quinlan and Bennett were found guilty of 16 representative charges of supplying equipment or material capable of being used for the cultivation of cannabis at their stores throughout the country.

On one of the charges, relating to the Glenfield store, Quinlan was found not guilty but his companies, Stoneware 91 and Hydroponics Wholesalers, were found guilty.

Business manager Ricky Cochrane, distribution manager Andrew Mai and South Island manager Paul Barlow were earlier found not guilty on all charges.