Farming mountain pepper wasn't what Tim Wimborne and Meraiah Foley expected they would be doing when they returned from working in Singapore a few years ago.

But by chance they discovered they had native Australian mountain pepper growing on their property near Braidwood on the NSW Southern Tablelands.

"In 2015 we had an ecologist do a survey on the property and she casually mentioned you've got a lot of native pepper here," Ms Foley told ABC Radio Canberra.

"We're not ecologists. We're not farmers. This was a lifestyle block and we said: 'What's that?'

"We had owned the property for almost 20 years without even knowing it was there."

They found 2,000 Tasmannia Lanceolata plants growing on their 40-acre property on the edge of Budawang National Park.

While endemic to Tasmania, it is rare to find large amounts of mountain pepper growing naturally on the mainland.

"It needs specific soil, a specific climate and rainfall, a specific type of forest and other trees it grows near," Mr Wimborne said.

"Our property just happens to be a nexus of all the things that it likes, and you move less than a kilometre from our place and it won't grow."

Intrigued by the native bush food, the couple, who both spent the past 25 years working in journalism, started educating themselves on how to harvest and use the rare spice.

"We've been doing it for a year-and-a-half and it's a very steep learning curve," Mr Wimborne said.

The berries form in spring and change colour from green to red to dark purple to almost black. ( Supplied: Tim Wimborne )

While the wild plants look after themselves, Mr Wimborne said harvesting was very labour intensive.

"It's very slow; it's all done by hand.

"We have friends that come and help us."

Mr Wimborne and Ms Foley are in the process of cultivating a plantation of 3,300 plants propagated from trees on the property.

And as far as they know, they are the only ones harvesting and cultivating mountain pepper in New South Wales.

"Because this industry is in such early stages, there is very little information available about what conditions are favourable to grow it in a propagated, cultivated situation," Ms Foley said.

"It's a great big experiment really."

Much stronger than regular black pepper

While called mountain pepper, the plant actually produces berries and is a completely different species to black peppercorn.

"It does have that slightly fruity taste that is associated with a berry, but then it has this very kind of slow onset heat that begins to develop on your palate about 10 or 20 seconds after you taste it," Ms Foley said.

"It's quite peppery; it's much, much stronger than a regular pepper," Mr Wimborne, who is also a qualified chef, said.

"We do warn people to experiment with it in small amounts when they start out."

The berries can be dried and ground to use as a black pepper substitute or to add a spicy bush food flavour to curries, meat dishes, salad dressings and even chocolate.

The leaves are also edible and serve as an alternative to bay leaves in cooking.

Mountain pepper is high in antioxidants and also contains vitamin E, zinc, magnesium, calcium and iron. ( ABC Radio Canberra: Penny Travers )

The polygodials present in mountain pepper have been found to have anti-microbial and anti-fungal properties.

"It's been identified as a potential natural food preservative," Ms Foley said.

"And there is tremendous interest in the health benefits."

Growing demand for native pepper

About 95 per cent of the mountain pepper industry is sourced from the wild, with only a handful of plantations in Tasmania and Victoria.

The industry is estimated to produce only about 10 tonnes of dried pepper annually, most of which is exported to Europe.

Of the 2,000 plants on Mr Wimborne and Ms Foley's property, about half are female and produce berries.

They expect this year's harvest, currently underway, will yield about 100 kilograms of berries which equates to only 25 kilograms of dried pepper.

"We've been contacted by people in the region who want to sell local mountain pepper and they're like, 'Can I buy 50 kilograms?' And we have to say, 'Not yet'," Ms Foley said.

100 kilograms of fresh berries equates to about 25 kilograms of dried pepper. ( Supplied: Tim Wimborne )

Chris Read, a Tasmanian mountain pepper producer and a former director of Australian Native Food and Botanicals, said there was strong demand for the native spice.

But he said uneven supply had so far restricted the industry's growth.

"Supply is very lumpy because the natural cycles tend to be very extreme," he said.

"There's a large production one year and then there'll be at least two years where there's almost nothing or very little to harvest."

As more plantations come on board and supply becomes consistent, Mr Reid expected the Australian mountain pepper industry would expand into new markets both domestically and internationally.