'Scratch and sniff' cards will be posted to households in Hull and the East Riding to help residents sniff out cannabis farms in their communities.
The cards, which will be distributed by the Crimestoppers charity and Humberside Police, replicate the smell of cannabis in its growing state.
Crimestoppers has launched the campaign after the number of cannabis factories in the UK grew by an estimated 15 per cent in 2011-12.
It says more and more factories are now being found in residential areas, rather than in commercial or industrial properties.
People who suspect cannabis is being grown in their neighbourhood are being encouraged to report the details anonymously on 0800 555 111, or at www.crimestoppers-uk.org.
The group's chairman Lord Ashcroft said: "Those who are cultivating cannabis tend to be involved in other areas of crime and are often involved in related gang crime and other violent crimes involving firearms.
"We want to help put an end to this and the funding that cultivation provides to serious organised crimes like human trafficking and gun crime."
Andy Bliss, of the Association of Chief Police Officers, said: "We know that many people don't realise that the empty, rundown house or flat on their street with people coming and going late at night may actually be a commercial cannabis farm.
"It's not just the stereotype of the remote rural set or disused industrial estate unit.
"The Crimestoppers campaign will help members of the public to recognise the signs and smell of a cannabis farm. The police will use the intelligence generated by the campaign to help build on recent successes in tackling this issue."
