The UK free-to-air broadcaster announced the deal this morning.
The initial payment will be followed by another payout depending on the production company’s performance over the next five years. It reported a profit of £2.5 million last year.
ITV’s content arm, ITV Studios, and The Garden inked a development deal back in 2011 and ITV Studios Global Entertainment sells most of the producer’s shows.
ITV said the deal was part of its ongoing five-year transformation plan.
Kevin Lygo, managing director of ITV Studios, said: “The Garden has grown rapidly and achieved an enviable reputation for outstanding delivery of innovative, ambitious documentary series for the BBC and Channel 4. A key focus for ITV is to develop hit programmes which we can then export globally and The Garden already has an impressive track record.”
The Garden was launched in June 2010 by Nick Curwin and Magnus Temple, who previously founded Firefly, the UK producer that was sold to Shine in 2007 for £10 million.
Curwin and Temple said: “Being part of ITV will help us grow further in the UK and, in particular, to achieve our international ambitions. We will be working more closely with ITVS whilst continuing to concentrate as hard as ever on our important relationships with Channel 4 and the BBC.”