A robber who threatened an elderly florist with a replica gun has been jailed for five years.

The sentence was meted out minutes after Home Secretary David Blunkett officially unveiled plans for a five-year minimum sentence for illegal possession and use of firearms.

The Government has promised to get tough on those who carry illegal arms to combat the growing teen gun culture, following the New Year killings of Latisha Shakespear, 17, and Charlene Ellis, 18, in Birmingham.

Yesterday's sentence was welcomed by the 77-year-old victim of the terrifying raid.

Lewes Crown Court heard how Gavin Dumbrill, 21, burst into the flower shop in Horsham and asked for a bunch of roses.

As florist Norman Poile wrapped the flowers, Dumbrill held a gun inches from his head and demanded cash.

Dumbrill, 21, of Park Street, Horsham, fled with £120 takings from Stone Edge Nurseries, in Park Terrace, and spent the cash on drink and drugs.

He was arrested a few days later.

He admitted charges of robbery and possessing an imitation firearm in October.

The court heard when Dumbrill threatened Mr Poile, who has run his business for 36 years, he at first thought the robber was joking.

Jos Greenhow, prosecuting, said Dumbrill produced the gun from his jacket pocket and shouted: "Give us your money."

But the florist thought it was a joke and replied: "You are kidding."

After his arrest Dumbrill, who has no previous convictions, told police he had committed the robbery because he was depressed and bored. Sentencing had been adjourned for a psychiatric report after Dumbrill said he had heard voices in his head which told him to commit the offence.

But the report said Dumbrill did not suffer from mental illness and it was more likely he committed the offence because of financial pressures.

Judge Anthony Scott-Gall told him: "You targeted an elderly florist who had conducted a modest business for very many years.

"He must have been terrified when you pulled a gun on him.

"That poor man must have felt absolutely frightened and terrified."

Dumbrill was sentenced to five years' jail for robbery and a concurrent two years for possessing the replica gun.

Grant Van Stone, defending, said Dumbrill was a man of good character before the offence. He had been on anti-depressant medication.

Mr Poile, who is still running his business, said he was satisfied with the sentence.

He said: "It was scary while he was here. It was the first time anything like that has happened while I have been in business.

"If he shoots me at my age, he shoots me."

Mr Blunkett will meet police and the Crown Prosecution Service on Thursday to discuss the rise in gun crime.

He also intends to introduce a five-year sentence for carrying a weapon as an amendment to the Criminal Justice Bill which is currently going through Parliament.

At a briefing yesterday he said: "While we already have some of the toughest gun laws in the world, there has been an unacceptable increase in the flagrant use of guns in crime across the country.

"We will not tolerate an escalation of the number of guns on our streets."

Senior police officers have been calling for the five-year minimum for some time amid fears of a descent into US-style violence.

They say guns are increasingly seen as a status symbol, even as a fashion accessory, among teenagers living outside the law.