The public gallery was crowded with supporters - some of whom had to stand.
As well as the sentence, Quinlan could still lose his million-dollar properties - one north of Auckland and the other in Queensland.
The Crown has filed papers in the High Court at Auckland to restrain the 53-year-old's $1.3 million home at Gulf Harbour, north of Auckland.
The property's official valuation describes the four-bedroom house as being in an "exclusive subdivision" known as Le Grande View.
With spectacular sea views and a "gourmet kitchen", it is billed as "a superior quality executive home".
Crown lawyers have also restrained his $1 million Queensland property that includes a spa pool and swimming pool.
A bank account in Quinlan's name holding A$189,352 has also been frozen, according to the court file released to APNZ.
Police affidavits show authorities went to great lengths to discover Quinlan's assets, including secretly downloading information from a cellphone belonging to Quinlan's wife as she passed through Customs.
Quinlan did not oppose his properties being restrained but in an affidavit filed with the court he said there was no "concession that the properties in question were in any way contributed to by criminal proceeds".
The applications date back to 2010 - soon after Quinlan was arrested as part of operation Lime.
During the police investigation, undercover police officers saw some staff members smoking cannabis, and others were willing to sell seedlings and the finished product.
More than 25 staff, including an area manager and the operations manager, have been convicted of drugs charges but the Crown said the drug offending went right to the top.
In a separate legal move, the Crown also sought to seize Quinlan's companies Hydroponic Wholesalers and Stoneware 91 - the supply and retail arms of Switched on Gardener.
The two companies were also convicted of drugs charges and have been fined $125,000 each.
The Crown said the companies were an integral part of Quinlan's offending. Quinlan is opposing the move.
The application - known as an "instrument forfeiture" - was made under the Sentencing Amendment Act. An asset can be forfeited if considered an "instrument of crime", although a judge can decline the application if the seizure would cause undue hardship to offenders or their families.
However, Judge Wiltens declined the application.
The Switched On Gardener business was born in the early 1990s when Quinlan and his brother opened the first store in the west Auckland suburb of Henderson.
From those modest beginnings sprang a business that eventually expanded nationwide with 16 stores and an annual turnover estimated to be $10 million. Switched on Gardener general manager Peter Bennett told the trial that up to 14,000 customers a month passed through its doors.
The court file shows that between November 2008 and July 2009 the turnover for Stoneware 91 alone was over $6.6 million.
Three Switched on Gardener employees were acquitted of all charges. They include business development manager Ricky Cochrane, distribution manager Andrew Mai and South Island manager Paul Barlow.
