A landlord tipped off the police when he discovered a tenant was growing cannabis plants in his Motherwell flat.
Officers searched the property and found 93 plants, worth £15,000, Hamilton Sheriff Court was told.
Maciej Staniewski (28) admitted producing cannabis at the flat in Addie Street between April and July last year.
Callum Forsyth, prosecuting, said the landord went to the flat to confront Staniewski after hearing he was cultivating the plants.
He waited outside for his tenant to return home, then followed him into the flat where he saw the evidence for himself.
The landlord contacted the the police and when officers arrived they were met by an “overwhelming” smell of cannabis.
As well as the plants, they found equipment such as tents, lights, heaters and plant food usually associated with such a cultivation.
Sheriff Ray Small called for background reports and deferred sentence until April 27. Staniewski remains on bail.