More than 1.4 million kilograms of pecans have been shaken, scooped and sent to the processor from Australia's largest pecan farm, Trawalla, in northern NSW — but it wouldn't have been possible without the casual harvest team of mostly backpackers.

After a "challenging year", pecan business manager for Stahmann Farms, David Reibel, said he felt lucky to have a harvest at all, and even luckier that he secured the workforce before the COVID-19 pandemic closed national and state borders earlier this year.

"We need 40 to 50 casuals for each harvest season, so ... there was going to be potentially trouble sourcing staff and getting them to move interstate," Mr Reibel said.

Stahmann Farms, at Pallamallawa just east of Moree, brought in the casual harvest team in March and offered them a month's additional farm work and accommodation while they did 14 days' quarantine on the 700-hectare property.

"We just decided to bring them back a month earlier and provide that extra work to guarantee that we had that workforce available when harvest was ready to happen," Mr Reibel said.

The team does two shakes of the mature trees, first in May to see the early maturing nuts come loose, and again in late June for any nuts that ripen later.Mr Reibel said most of the casual harvest roles are filled by backpackers, who are "reliable and punctual".

This year the team came from Europe, South America, Indonesia and New Zealand — but were all in Australia when the borders closed.

"A lot of them have skills that don't apply to this sort of work, you can have engineers and all sorts of people working for you," Mr Reibel said.

"Typically they just want to work, want to get some hours up and are keen to work and that's what a lot of farmers need, to get in and help with that harvest and help get the produce off."

New Zealander Megan Carrington was travelling South-East Asia with her partner at the start of the year, but they decided to fly to Australia when COVID-19 started putting pressure on international travel.

"We had to do quite a bit of isolation when we got back — two weeks in Sydney, then two weeks when we got to the farm because they were very cautious about people coming that had been travelling or just in other parts of Australia," she said.

The pair had planned to return to Trawalla after working through the 2019 harvest on their travels.

"It's a good little money make honestly, because obviously you're so far out of everywhere and I really enjoy meeting the people that come and work here, also the permanents are pretty awesome so it makes it an easy choice to come back."

Ms Carrington has been travelling and working around the world since she left New Zealand at the end of 2016. While in NZ, she mostly worked in caregiving and hospitality roles.

"I hadn't done anything on this scale before, I worked with my mum for a while, who was a gardener, but we didn't use machinery like they do here," she laughed.

"But we definitely didn't shake a tree."

Trawalla is the largest pecan farm in the southern hemisphere and supplies most major supermarket chains in Australia and has a significant export presence globally.

"The Asian market is growing, the world's middle class is increasing in size and their demand for healthy, safe produce will increase, and that's where we fit the bill," Mr Reibel said.

To meet demand, the farm is now expanding after acquiring land on either side of the current property.

"We have about 40,000 trees to go into the ground over the next six weeks, so our harvest crew is now pretty much turning into our planting crew," he said.

"We'd hope that five years after planting these [two-year-old] trees out in the orchard they'll be worth shaking and we'll do our first harvest then."