The call comes as chief police officers report a doubling in cases of homegrown cannabis.
A report by the Association of Chief Police Officers (Acpo) said the amount of cannabis being grown in the UK is at its highest ever level.
Commander Allan Gibson, Acpo's lead on tackling cannabis cultivation, told Sky News pressure must remain on drug growers.
"This is organised crime, it's getting invovled in what they see is lucrative business," he said.
"We need to make sure the risks to them are great - that they're being found out and they're crops are being taken away from them, but also the risk of going to prison and having their assets taken away from them."
But Professor Sir Ian Gilmore, a former president of the Royal College of Physicians, said drug laws should be "reconsidered with a view to decriminalising illicit drugs use".
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