TVNZ formally launched its first prime-time Maori-language reality show yesterday.

Bailey Mackey, a former TV3 reporter, has produced One Land, a six-part series which sets three families in 1850s New Zealand.

One family speak only te reo, one are Pakeha and one are Maori but not connected to their culture.

The Maori families live together in a traditional pa along the Kaiaua coast while the Smith family from Christchurch live as working-class settlers.

Episodes have between 20 and 25 per cent te reo content and will run in the 7.30pm slot on TV One from Sunday, December 13. The reo content and scheduling are a first for the station, managers say.

Mackey said TVNZ had been criticised in the past for its treatment of Maori programming, but the prime positioning of One Land needed to be recognised.

"Our state broadcaster is often maligned but I think they've been really brave with this.

"I'm massively proud because Maori is our national language and we'll hear it."

One Land looked closely at how cultures interacted, he said.

Billy T. James did it with his Captain Cook sketches two decades ago and this reality format would do the same, Mackey said.

The living quarters, tools and clothing were meticulously researched but living under conditions where the main concern was gathering enough food for survival had caused a heap of stress for the participants.

But there's plenty of humour while they try to acclimatise.

Matthew Smith, 20, represented his family - mother Tanya, father Lindsay and siblings Marshall, 22, Nadia, 12, and Conrad, 10 - at the launch yesterday.

In clips, the family struggle with lack of food, until a trader who sells at exorbitant prices turns up.

The family pick up meat and oatmeal and a few other necessities, but can't afford any lard.

Matthew thinks quickly and swipes it. His mum tries to justify the situation but Matthew sets her straight. "He didn't leave it here, I pinched it."

The Smiths salve their conscience by slicing a bit of fat off before sending it back to the trader.