From Baby Boomers to Generations X, Y and Millennials, Australian workplaces have never been more generationally diverse.

The number of Australians working past the age of 55 has grown exponentially in the past 40 years and there are now more than half a million people over the age of 65 in full-time and part-time work.

The age range can prove to be a challenge, but according to workplace researcher John Buchanan there are benefits for businesses with older workers.

"I think there's a productivity dividend to be had if we can harness that practical wisdom better," he told 7.30.

"Practical wisdom can only be acquired through the course of time — you can't do a practical course.

"It's embodied in people who've experienced problems in the past and have reflected on it."

Ageing like fine wine

Ruby Osborn, Chester Osborn, d'Arry Osborn and Alicia Osborn all work together at D'Arenberg winery. ( ABC News: Carl Saville )

At the d'Arenberg winery in McLaren Vale, south of Adelaide, the workforce spans nine decades.

"We've got 15-year-olds working as concierge down in the gallery," owner Chester Osborn said.

"There's quite a few 20-year-olds … lots of people are mid-20s to 50, and a few of us 60-year-olds.

"And my father at 92 still comes to work every day."

That is d'Arry Osborn, who helps out collecting the mail and doing other odd jobs.

But the senior Mr Osborn happily acknowledges his shortcomings.

"I'm computer illiterate," he said.

"I can only work by phone and I hate computers and I'm frightened of it whenever I look at."

Andrew Tothill, 57, says he enjoys mentoring younger workers, such as Christine Huller, 28. ( ABC News: Carl Saville )

His granddaughter, Ruby Osborn, helps out whenever she is around.

"Pretty much everything, anything that I learned, was from all of the older, experienced people," she said.

"But it was actually so nice, because growing up we were running around the wineries, and I knew all [dad's] work people were just his work friends."

Vineyard supervisor Andrew Tothill is 57 years old and regularly teaches people more than 30 years his junior.

"That's the bit that I find really enjoyable," he said.

"You get a young person come on board. You're mentoring with, not only work issues, but sometimes you get to life skills as well."

Learning new tricks

Roydon Featherstone says he sometimes turns to older colleagues for advice on solving problems. ( ABC News: Carrington Clarke )

At Taylor Brothers ship builders in Hobart, the staff range from 19-year-olds to workers born in the middle of last century.

In the boatshed beside the Derwent River, Roydon Featherstone and Samuel Brito are going through a ship plan.

There's more than three decades in age difference between them, but they clearly work well together.

"I've learnt a few tricks from him," Mr Featherstone, 19, said.

"Sammy's obviously got years of experience. If I'm not doing something that's working, he's probably got a million different ways to fix something that I can't figure out."

But Mr Brito, 53, is learning too.

"It's becoming a bit more difficult for me with new machinery, because its more electronic, more buttons on the machines," he said.

"But you know, they manage, we help each other.

"For me, personally, I love to teach young generation. It's the future."

The problem of underemployment

Samuel Brito and Roydon Featherstone working together at Taylor Brothers ship builders. ( ABC News: Carrington Clarke )

Mr Buchanan recognises there are limitations to working beyond retirement age for some people.

"If you're a labourer, your body can take only so much labouring," he said.

"The retirement age was set for that reason — people can't just keep on bashing metal or laying bricks until they die."

But there remains the problem of underutilisation for many of those who chose to carry on working, with some older workers wanting to work longer hours.

Unemployment in this category, for those who want to work full time, is close to 50 per cent.

"We've had about 27 years of uninterrupted growth, but what people neglect is that Australia has one of the highest levels of underemployment in the world," Mr Buchanan said.

"Where you've got unemployment and underemployment together constituting 15 per cent of the workforce, that means there's not much pressure on employers to do things differently."

At d'Arenberg winery, Chester Osborn says it is invaluable to have input from younger generations.

"It's great seeing older people and younger people interacting," he said.

"It's fantastic because there's always excitement from both sides from the different ways."