Two men have been arrested and released on bail after a drugs warrant was carried out in South Oxhey this week.
The warrant was executed on Wednesday when police visited the Hayling Road property.
A 23-year-old man was arrested at the address and a 31-year-old was later arrested in Fraser Road, in Greenford.
Both have been arrested on suspicion of possession with intent to supply Class B drugs.
Hertfordshire Constabulary believe that the substance found was cannabis.
The two men have been released on police bail and were told to return to Watford Police Station on May 8.