Market trader Thomas Anthony Birchall claimed that he drank a lot of cannabis tea for health reasons.
He used four grammes a day which he drank in tea to aid his asthma, the pain from his slip disc and other conditions, he said.
Birchall claimed that all 109 plants found growing in an industrial unit he rented in North Wales were for his own use.
But his story was rejected at Mold Crown Court.
Judge Rhys Rowlands said that there was simply too much cannabis for it to be for his own exclusive use and said that some of it would have been sold on.
Birchall (51) of Leicester Street in Warrington, who admitted a production charge, received a suspended prison sentence.
The court heard how he rented an industrial unit from Conwy Borough Council on the Mercury Trading Estate at Kinmel Bay.
In September of last year council officials forced their way in after a complaint from the tenant in the unit next door about the smell of cannabis and the heat coming through the adjoining wall.
They found that the electricity meter had been by-passed and that there were five zones under lighting including mature plants, a mother plant, and cuttings or seedlings.
Prosecuting barrister Brett Williamson suggested that the estimated street value of the potential yield was between £30,500 and £91,000.
That was not accepted by the defence, Jonathan Austin, defending, who said that any amteur gardener would know that up to two thirds of the seedlings might fail.
Judge Rowlands, who heard expert evidence, said that the 31 established plants and the 78 cuttings or seedlings at the most conservative estimate would give the defendant 107 weeks worth of cannabis.
Birchall said in evidence that he drank a lot of cannabis tea daily for pain relief and that he would take flowering buds home to do so.
He received an 18 month prison sentence suspended for two years and he was ordered to carry out 200 hours unpaid work.
An investigation under The Proceeds of Crime now takes place to see how much, if any, of his ill-gotton gains can be confiscated.