Coffee has been grown on Atiu for around 200 years, having been established by the early missionaries in the hope of creating a commercial crop. As we stood in the plantations, Juergen explained that by 1865 the Cook Islands were exporting £30,000 worth of coffee a year, making it a major industry.
But since then the coffee business has had its ups and downs, and when Juergen arrived on the island in 1984 planning to open a starch factory, the plantations were abandoned and overgrown.
The starch factory plan fell through because it wasn't possible to guarantee a consistent power supply on Atiu so, at the suggestion of then-prime minister Sir Tom Davis, Juergen looked at reviving the island's coffee trade.
"Just as well," said Andria Eimke, Juergen's artist wife, "coffee is nice-smelling. Starch smells like vomit."
Juergen took up Sir Tom's challenge and, in conjunction with local landowners, set up the Atiu Coffee Factory, imported processing machinery, cleared the old plantations and began producing roasted coffee beans.
Today the company manages 39ha of coffee plantations - as well as buying beans from some small independent growers - hand-picking around 17 tonnes of beans annually. These are dried in the bright Atiu sun for at least 250 hours, stored for a minimum of six months to let the flavours develop and roasted to order, producing some 4.5 tonnes of roasted beans.
The coffee is packed in sealed bags and sold to restaurants on Rarotonga or by mail-order and through the company website to customers around the world.
Juergen - who admits "I was always a coffee freak" and drinks about five mugs a day - reckons the reason for Atiu coffee's success is the special flavour.
"Early on we sent some of our beans away for analysis. The report was that the beans were a funny shape because the plants had not been cared for properly but the juice was wonderful. They are high in flavour and low in caffeine."
That's a nice story but, of course, the proof of the coffee is in the drinking. For this we went to Andria's Atiu Fibre Arts Studio where she displays her work - mostly in fibre but some jewellery - which blends Cook Islands' motifs and materials with European designs and techniques.
There we tried the factory's dark and light roasted beans. I'm no coffee aficionado, but I thought it was excellent. My wife - who is more picky about her coffee - agreed. She preferred the light roast. I liked the dark.
"I prefer the dark roast myself," said Juergen. "It's got more flavour and less caffeine."
CHECKLIST
Getting there: Air New Zealand flies to the Cook Islands and Air Rarotonga flies from Rarotonga to Atiu every day except Sundays.
Where to stay: Atiu Villas has self-contained villas and organises local tours.
Coffee: You can find out about Atiu Coffee Tours and buy coffee at atiu-coffee.com.
Further information: See cookislands.travel.
Jim Eagles visited Atiu with help from Cook Islands Tourism, Air Rarotonga and Air New Zealand.