By Leigh Mytton BBC News Online entertainment staff

Celebrity gardener and housewives' favourite Alan Titchmarsh and I are talking about the price of fame.

He says it doesn't bother him.

"The people who come up to me in the street are paying my wages."

But he says he worried about his daughters when they were tiny.

"I felt sorry for them when they were small. Remember when you were little and you were hanging off your dad's trousers?" he says, gently grabbing my leg and doing an impression of a three-year-old.

I realise I am living many a woman's dream.

'Absurd'

We meet in the cool surroundings of a London hotel. Tichmarsh, 53, is promoting his autobiography, Trowel and Error, which, it seems, came about after much soul-searching.

"I am a relatively private man - an absurd thing to say when you are in TV, but I've always kept my private life private," he says.

It's such a lovely thing to make a garden out of nothing in a couple of days

Alan Titchmarsh

"I've kept my family out of the limelight. You think: 'Am I thrusting it all forward? Why am I doing it?', but at least I'm in charge this way. I can say how things were as I saw them."

It is a pivotal time in Titchmarsh's life.

He has said farewell to the shows which made him an institution, Ground Force and Gardeners' World, and he is moving out of Barleywood, his Hampshire home of 20 years.

It sounds like a mid-life crisis, but it is a mid-life blossoming, he says. Is he intending to retire? "Not bloody likely," he replies, laughing.

'Nagged'

He is looking forward to a new series of How To Be A Gardener, is embarking on a natural history TV series and has been commissioned to write a further two novels.

"I decided to go while it's still good," he says of Ground Force.

Asked how his co-presenters, Charlie Dimmock and Tommy Walsh, will cope as a duo, he says: "Absolutely fine. They'll love not being nagged for a while, then they might miss me."

Titchmarsh has a blooming media career

Ground Force came in for some criticism recently, when the BBC was criticised for "dumbing down" its 11 September coverage by sending the TV show to New York to create a garden at Ground Zero.

But Titchmarsh felt the event was a valuable occasion.

"It's such a lovely thing to make a garden out of nothing in a couple of days. It's quite moving," he says.

He is upbeat about leaving Barleywood, which featured every week on Gardeners' World.

Tightlipped

"We're staying in the area. We've found a lovely old house, with two acres. It was owned by a good gardener. There are about three beds and they are beautifully planted, so I shall work with them."

He starts filming the natural history series in November. "It's about why our islands are the way they are in terms of plant life, geology and wildlife.

Ground Force is one of BBC One's most popular shows

"We are coming through the formation of the islands to the dinosaurs to modern climate and vegetation."

On his upcoming novels, he remains tightlipped, but has plenty to say about the sexy passages in his previous fiction, which caused a media storm.

In 1998, he was nominated for a Literary Review Bad Sex Award for his debut novel Mr MacGregor.

"Readers never seem to have any problem with them," he says. "Falling in love, making love and being passionate are part of the dynamics of any relationship and sometimes you need to show how it works. I hope it's sensuous and slightly erotic, but it's not sordid and grubby."

He is delighted, however, at being credited with making gardening sexy, influencing many 20-somethings to pick up a trowel.

'Pleasure'

"It hasn't surprised me that they find it interesting. I'm just thrilled to bits that they have realised that. It's not about chores and learning Latin names. Don't be daunted. Get out there."

He says his career highlights are doing Nelson Mandela's garden for Ground Force and getting his MBE, when the Queen famously remarked: "You have given a lot of ladies a lot of pleasure."

"She's a good egg," he says, admitting he is "absolutely thrilled but totally disbelieving" of his heartthrob status.

Trowel and Error is out now