Two Dover conmen ripped off vulnerable homeowners, by carrying out work which was “poor, ineffective, shoddy... and sometimes completely worthless”.

Greedy Roger Knight, 42 and pal Wayne Smith , 48, raked in thousands of pounds by offering gardening services in Walmer and Folkestone.

Now a judge has heard how the cowboy landscapers had also been turned over three years ago in an episode of the BBC consumer show Watchdog.

But all the two fraudsters did was to switch names.... and continued conning people – including a 95-year-old Walmer pensioner who is nearly blind, Canterbury Crown Court has heard.

Today, Judge Adele Williams jailed the ringleader Smith for 30 months and Knight for two years after telling them: “These were mean and despicable offences, a confidence trick to target vulnerable people, gain their confidence and then make extortionate charges and cynically defraud them.”

“These were mean and despicable offences, a confidence trick to target vulnerable people, gain their confidence and then make extortionate charges and cynically defraud them" - Judge Adele Williams

Knight, of Castle Street, Dover and Smith, of Old Folkestone Road, Aycliffe both admitted charges of fraud, laundering money and breaches of the Unfair Trading Regulations legislation.

Prosecutor James Dennison said: “These two, aided wittingly and unwittingly by others, engaged in a course of conduct of ripping off members of the public.

“Their victims included the elderly, vulnerable and those not looking out for what was round the corner...and what was around the corner were these two dishonest people.”

In 2012, Watchdog set up a sting with an actress posing as a frail pensioner and filmed her being ripped off by Smith's company, WC Smith.

After the show was aired the two re-sprayed their van and carried on defrauding people under the new name of R N Knight Landscape Gardeners.

One victim James Collett, who was 93 at the time, hired them to carry out work at his home in Neville Gardens Walmer.

The prosecutor said that it started with a £400 contract...but by the end the pensioner had handed over more than £20,000.

An expert later valued the work done by the con artists at £1,700...but Mr Collett’s son later had to hand over another £4,000 to rectify the botched job.

Lee Somerset, of Tritton Gardens, Dymchurch was charged £21,000 for work which should have between £1,800 and £3,000.

Mr Dennison said Mr Somerset believed the £16,000 repair work had been carried out to his home – but it hadn’t.

"The sentences passed down today to Smith and Knight are a real deterrent for people attempting to rip off vulnerable people in Kent..." - Mark Rolfe, trading standards

And when the householder returned from a trip to America and was “jet-lagged” they charged £4,800 for fallen trees - work which should have cost £780.

And William Roberts and a neighbour, who has since died, handed over hundreds of pounds for work at their homes in Swaynes Way, Eastry.

After the sentencing, KCC's trading standards manager Mark Rolfe said: "The sentences passed down today to Smith and Knight are a real deterrent for people attempting to rip off vulnerable people in Kent.

"It should be a clear warning to people that the authorities in Kent, trading standards and the police, will work day and night to make sure that people who attempt this kind of crime will be caught and that's what we do to protect the vulnerable people in our communities.

"If somebody's knocking at your door, our advice to consumers is to say no, thanks very much and to consult a proper tradesman.

"In Kent we have a partnership scheme with Checkatrade where all of the traders are tested by trading standards and approved by us.

"So, we would say to the public avoid these rogue traders, don't get caught out by them, go to Checkatrade and find a trader in Kent who you can rely on."

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