The couple have a forest of 800 oak trees at their 350ha arable farm, which has yielded its highest underground bounty ever.
"And next year, as long as we do everything right, will be bigger again," Robert said.
For the three-month season, which began last month, the bounty so far was five times what it was last year. The level each year was expected to increase exponentially and then plateau. One tree alone had already yielded 4kg.
The couple established Grice Truffles about 11 years ago, planting oaks which had their roots inoculated with truffle mychorrizae. The first truffles were harvested in 2014.
Helping with their big haul this year is Ivy the 15-month-old beagle. Truffiere dogs help find truffles by sniffing them out, and letting their owners know whether they are ripe and ready to be dug up. Although she is young and still being trained, Ivy has so far proven to be a star on the job.
Robert said in the truffiere world, dogs good at their jobs become more well known than the owners.
It seemed Ivy was following in the footsteps of her predecessor Cluedo, a former airport biosecurity beagle who served with Grice Truffles for about three years before dying in 2022.
Grice Truffles has another thing on its side — an old pair of Yeezy slides owned by Robert. He said the softness of the rubber sole enabled his feet to feel truffles poking through the ground.
"I didn’t buy them with that intention, I just found that happened," Robert said.
Finding the often elusive black delicacy is half the work when it comes to being a successful truffiere. American rapper Kanye West could not have known just how helpful the shoes would be for this purpose when he collaborated with Adidas to create them.
Grice Truffles is one of just a handful of truffieres in Mid Canterbury. It supplies to restaurants around New Zealand. This includes one Mid Canterbury restaurant, The Rabbit in Ashburton, which it started supplying to this month.
It was their love of the taste of truffles and the challenge of growing them that attracted the Grices to the industry. Robert first became fascinated by this about 30 years ago, as he tasted the delicacy for the first time while travelling in Italy.
"The chef brought out some pasta with truffle on it. I was just intrigued. I liked it.
"I was also taken by the mystique of the whole thing."
His third generation property turned out to be the perfect place for growing them, due to Mid Canterbury’s favourable soils and climate. So far, their operation had not made a profit, but was "probably" about to become profitable as the yields continued to grow.
"It’s got nothing to do with making a profit. If someone is going to do it for that reason, they will be disappointed," he said.
"I say to people ‘It’s a bit like groper fishing. You don’t know what you are going to get, but you don’t get sea sick’."
Jane said she enjoyed getting out with Ivy and finding truffles.
"It’s really cool out there, the ambience, it’s next level,. There’s fantails and other birds."
The couple are planning to soon plant about 50 pine trees inoculated with saffron milk cap mychorrizae, so the delicious mushrooms will grow around them. They will supply the mushrooms to some of their restaurant clients. This has also been inspired by their passion as foodies.
"Just because it tastes good, everything is because it tastes good," Robert said.