The Teviot Valley once thrived with gold miners, but now red gold is being grown in a small patch of the area.
Wendy King and Graham Strong, of Wynyard Estate, near Ettrick, are planting crocus corms on a new 1.2ha plot, which will quadruple their output of saffron.
Last year, they produced 2kg of the world’s most expensive spice on a 50m x 25m plot, but the expansion will boost that to 8kg. Ms King said 1kg of the spice fetched $30,000.
Dr Strong has a PhD in botany and has experimented under the soil.
Ms King said early results of those experiments showed an increased production of corms, meaning more flowers at harvest time.
Their saffron has the mark of the International Standards Organisation which measures colour, flavour and aroma.
Ms King said she believed a Te Anau saffron farm was the only other in the country to get that stamp of approval last year.
The extravagant price of the spice was partly because of a world shortage, she said.
"It’s also very labour intensive. You can never use machinery to harvest saffron."
Central Otago’s climate was perfect for its growth.
"They like hot, dry summers. They can handle down to -20degC. Although it’s been an extremely lousy summer, so I’ll let you know in February."
There were "quite a few" small saffron farms in the region, most of which grew it as a hobby, she said.
The couple moved to Central Otago from Dunedin in 2012 for a lifestyle change.
"I’m a chef by trade and with my partner’s PhD in botany, it seemed to be a perfect fit."
It was easiest to sell directly to customers and restaurants. If it was in a shop, they would have to compete with cheaper products, she said.
"There’s a lot of adulteration in the industry. All kinds of things can be put in. I’ve heard of people using parts of corn husks. In powdered form they can add things like turmeric."
Saffron was able to enhance other flavours, and was "all about the infusion", she said.
The pair made their own concoctions with salt, honey and jam, which they also sell.
However, the practice was not profitable until after the first three years, she said.
"Unlike what a lot of people think, it’s not a get-rich-quick scheme."
