POLICE searching a warehouse unit in Kent discovered a massive skunk cannabis factory cultivating thousands of plants.

At full production the enterprise could have netted the growers an annual turnover of between £1.9m and £2.5m.

Oliver Saxby, prosecuting, told Canterbury Crown Court there was a shortage of cannabis on the streets of East Kent after the discovery of the factory in Ramsgate.

Police arrested Stephen Rochester, 60, of Cliffsend Grove, Ramsgate, and Dennis Murphy, 40, of Bayliss Road, London, who in March admitted cultivating cannabis plants between January 2005 and May 2006. Sentence was adjourned for reports.

On Tuesday, Rochester was jailed for four years, nine months after being told by Judge Anthony Webb, that he had played more than a subordinate role and an undeniably significant one.

Had he been convicted after a trial, he could have expected a sentence in the region of 10 to 14 years.

Rochester was the grower and responsible for ensuring the project's success although he hadn't put any capital into it. He expected 10 per cent of the profits but the judge said he accepted Rochester actually received less.

"I am certain others higher up were involved. They are not before the court and those who are responsible for the investment and who reap the profits of such enterprises must realise they will receive long sentences if caught and convicted," said Judge Webb.

"It was a serious financial enterprise with extremely large financial rewards for those at the top of the organisation."

Sentencing Murphy to nine months, suspended for two years, with 120 hours community work, Judge Webb said only a custodial sentence was justified. Murphy's best mitigation was he had always accepted his responsibility.

Officers raided the warehouse on Ramsgate's Whitehall Road industrial estate in May and found 4,673 plants in various stages of growth and a full production unit with six growing rooms, drying and cutting rooms, warehouse area and living quarters with hydroponic set-up. The price per kilo was an estimated £3,000 to £3,200.

The warehouse had been rented by someone calling himself Mr Golden of Furniture International Limited using a mobile phone registered to Rochester.

The £14,500 quarterly rent was paid in cash. Rochester also rented two houses in Ramsgate for £750 and £1,500 a month, always paying in cash.

After his arrest, Rochester said he had been working in a smaller factory elsewhere and was asked to help out with a larger project.

The initial outlay was £70,000 and others were also involved. A lot of money had been invested in security gates at the Ramsgate premises.

Rochester said he had worked for a property developer who was also a drug baron and said Ramsgate was the biggest drug factory he had worked in.

John O'Higgins, for Rochester, said it was his first offence in 20 years and occurred at a time of domestic crisis.

He took up an option put before him "and like many, was beguiled by the chance to earn a little extra money but nasty people are involved in large scale criminality and things became more difficult."

His wife was an alcoholic and he moved from London and in time became the carer for his four children who would now go into care.

Murphy worked as a cleaner and cleared away waste in black sacks for £200 a week.

David Bedenham, for Murphy said although it was a significant drugs operation and Murphy had admitted his involvement, it was a minor role on the periphery.

He had been approached in a pub when he was out of work but didn't know drugs were involved until he started working at the factory and realised something illegal was going on but didn't give up the work.

"He is rather naive and vulnerable and cared for his disabled mother. At the time he had been out of work for about 12 months.

"He knows there is a real risk of custody but it would be disastrous for him," said Mr Bedenham.