Despite being around chickens all their lives, they were still learning more about them every day.
Mr Craig said his grandparents were keen adopters of cages for their hens in the days of post-war food shortages. It kept their birds safe and able to lay regularly.
Now, science and technology allowed poultry farmers to maintain the health of birds that lived largely outdoors.
Criticism of ''battery hens'' as a form of animal cruelty led, in 2012, to the National Animal Welfare Advisory Committee introducing a code of practice under which caged hens would be phased out by 2022. Farmers could opt for a colony system, a barn, or free-range.
The Craigs chose free-range sheds adapted from overseas examples. Commercial sensitivity prevented Mr Craig from divulging further information, but he said they were the only ones using that design here.
The doorways open from 10am to 9pm, letting the hens roam the surrounding paddocks as much as they liked. Some headed out boldly; others were ''shed-huggers''. Older hens tended to be more ''proactive'' than younger ones.
Because they were used to humans walking among them in the sheds, where their main food was supplied, they were not shy of people. Having spotted Mr Craig outside their paddock fence, an increasing number walked over, contentedly cooing quietly.
''They're curious all the time.
''In the initial stages we were watching the chickens to see what they were interested in. We want to make life more interesting and fun for them.''
They liked to scratch in pasture to find worms and insects, and also ate a bit of grass. A pasture management regime ensured it was kept longish but not too long.
Production was similar to caged hens, most laying an egg a day, Mr Craig said. The free-range birds were the same breed as those used across the industry.
The Craigs also run a cropping operation that provides all the poultry feed. A 24ha paddock of bright yellow oilseed rape alongside SH1, constantly being photographed by motorists, would be harvested in January and the seed sent to Pure Oil NZ in Rolleston to be processed into oil and extract.
''There's quite a nice synergy between poultry and cropping,'' Mr Craig said.
''We've got very good cropping farmers in North Otago. We have excellent arable soils.''
Herbert has long been associated with poultry where the cool, dry climate was ideal. It was once known as ''Feather Town''.
