A room at a four-star hotel in Ealing was turned into a "cannabis shop" by a couple who stayed in it for five days last February.
Staff became so concerned about the comings and goings from the room that they called the police, Isleworth Crown Court heard on Friday.
Zafran Khan, 25, of Haven Lane, Ealing, and Harriet Sheperd, 19, of Rosemont Road, Acton, admitted possessing cannabis with intent to supply it at the Ramada-Jarvis Hotel, Ealing Common, between February 2 and 7.
Prosecutor Richard Mandel said: "Staff noticed a lot of traffic in and out of that room and became suspicious and informed the police.
Police attended and found Ms Sheperd in the room.
"They searched the room and it became quite clear it was being used as a sort of shop for the sale of cannabis."
Mr Mandel said officers found 92 grammes of the drug 'skunk', digital scales, cling film, self-seal bags and £360 in cash.
Police then went to Sheperd's home and searched her bedroom, where they found two safes containing 51 grammes of skunk, ten grammes of herbal cannabis and £50 cashed.
The combined street value of the cannabis found was more than £800. While police searched the flat, Khan turned up at the hotel and was arrested.
Mr Mandel said: "There was quite a lot of CCTV showing him coming and going from the hotel room. He was heavily involved in the running of that cannabis shop."
Sheperd had not been in trouble before but Khan had previous convictions for possession of cannabis.
Ghalan Ahmed, mitigating for Sheperd, said she left school with six GCSEs and had now gained a place at Birmingham University, which she was due to take up in the autumn.
He added she was no longer in a relationship with Khan: "She apologises and will never appear before the courts again."
Defending Khan, Sarah Morris said he smoked cannabis over many years but was dealing to friends and friendsof-friends only.
Khan was jailed for nine months as 'the prime mover' according to the judge, Recorder Grace Amakye, who gave Sheperd a suspended sentence for two years, saying she was under the influence of her co-defendant. She must also do 150 hours unpaid work.