It was a tale to rival Jack and the Beanstalk when dabbling gardener Brian Barram threw some strange seeds into a flowerpot.

During the next few weeks curious stalks sprang out of the earth and just grew and grew and stretched up into the sky.

Now the unusual plants tower almost as high as Mr Barram's house and have become a legend worthy of a fairy tale among children in his neighbourhood.

Scores of youngsters have dropped by his home in The Lanes, Brighton, to take a peek at the peculiar plants.

Some people have even taken photographs of the strange purple flowers, while puzzling over their identity.

Even London Mayor Ken Livingstone once stopped to look at the tall cactus-like growth as he passed by, before asking neighbours what it was.

Mr Barram, 63, an Australian who has lived in England for more than 30 years, was given the unusual seeds by a friend three years ago.

The plant, a member of the Echium Pininiana species, is native to Australia and South Africa but not common in England.

Mr Barram put the seeds in a plant tub and left them to grow.

The seedlings were soon too big for the pot so he transferred them to his garden.

Since then, the plants have got taller and he does not know when they will reach their full height, although he says he is not expecting them to shoot through the clouds.

He said: "Everybody asks what it is in my garden. I haven't given it any special attention. It's a very unusual plant. I usually collect seeds and cuttings and try and grow them.

"These just kept on growing and growing and growing.

"They're not rare, but I can't imagine you will find many over here. I saw some at Glyndebourne, but they were only a paltry two or three feet. These are about 15 feet or more now. They have started to flower, so I imagine they will die after that and I will have to chop them down.

"I haven't got a very big garden, but I do pick up the odd plant or two. They're now as high as the bedroom on the first floor of my house.

"They're just a one-off, I don't think I will grow anything like it again. They're the only thing growing in the front garden. The leaves are ugly really, but what makes them interesting is that they are so unusual."

Mr Barram is now challenging other gardeners to grow taller versions of the plants and he hopes it will become an annual contest to rival the yearly search for the tallest sunflowers.