Allsopp and Fowler are old school friends from £9,240-a term Bedales School, where they once set the world record daisy chain length record.
UK Gardeners’ World presenters Joe Swift, Carol Klein and Alan Titchmarsh were rejected because of their strong regional accents.
A BBC source said: "The Yanks love the cut glass accents of Kirstie and Alys. Joe is seen as too ‘mockney’, while Carol and Alan’s northern vowels are unintelligible to the denizens of Alabama. The show will bring some English class to the tacky tradition of US gardening. The Americans also love Kirstie because she looks like Monica Lewinsky."
Barack Obama’s garden at the White House, Stephen Spielberg’s Jurassic Park-themed plot in Hollywood and Elvis Presley’s Graceland landscape will receive makeovers during the series.
The BBC setting up a US office in Hawaii to be run by veteran broadcasters Peter Seabrook and Lady Mary Keen.
But the Taxpayers’ Alliance has complained that the new venture is a waste of taxpayers’ money.
A representative said: "Setting up an gardening office in Hawaii would costs millions, while BBC jobs are being cut in the UK. It’s beyond the pale."
Allsopp’s sidekick, Phil Spencer, will also present alongside US favourite, ex-stripper Jamie Durie.
The BBC hope to roll out the show to other nations, as far flung as the Gabon, Antarctica and Libya.
Have you registered with us yet?
Register now to enjoy more articles and free email bulletinsSign up now