More than several plants will result in a "supplying" charge

The number of cannabis cultivations has risen by more than 60% since 2001.

Police attributed the rise to a perception that they had "taken their eye off the ball" after the drug was reclassified in January 2004.

Shopkeepers have also been warned that they face prosecution if caught knowingly selling drugs paraphernalia.

In 2001/2002, 52 people were reported to the procurator fiscal for cultivation, compared to 85 people in 2004/2005.

Detective Sergeant Kenny Simpson, of Strathclyde Police, said: "The number of people growing their own cannabis in the domestic environment or on a larger scale is increasing.

We're finding not only cannabis pipes being sold, but also grinders, snorting tubes and cocaine chopping kits DS Kenny Simpson Strathclyde Police

"When the drug was reclassified from class B to C, I think there was a perception that the police have taken their eye off the ball in terms of cannabis offences.

"The penalties are less for possession but the message that has been missed is that penalties for supply are now greater.

"If the cultivation is anything bigger than a few plants, the charge will be cultivation and supply, not cultivation and possession."

Snorting tubes

The force also warned shopkeepers of the consequences of knowingly selling products which may be used to administer or prepare controlled drugs.

Mr Simpson explained: "The shops are well known to the police through the Drug Awareness Officers that are in every division and members of the public.

"We're finding not only cannabis pipes being sold, but also grinders, snorting tubes and cocaine chopping kits.

Police say they know where drug-related products are being sold

"There's nothing to stop people selling pipes, but where there are pipes that are clearly designed for cannabis use, that is an issue we will look at.

"We have embarked on a phase of warning shopkeepers, that will be followed by enforcement."

Officers will now visit shops to offer guidance on the Misuse of Drugs Act 1971, which makes it an offence to knowingly sell drugs paraphernalia for the preparation or administration of a controlled drug.

Mr Simpson said that if the advice was not taken on board, the officers may return and shopkeepers ran the risk of being arrested with their stock being seized and used as evidence.

He added: "I would urge all shopkeepers to think of the impact on the community in which they are based. We are willing to offer advice and assistance regarding the legislation that impacts on the sale of these items."