But Mr Friar is no dealer, and this is no underground plantation. The 66-year-old and his wife, Wendy, are the proud owners of Australia's first licensed industrial hemp crop to be grown in an urban area.

"I'd prefer you didn't publish exactly where we are," he says.

"Even though this is no good for smoking, you can imagine what would happen if people found out."

The Friars are hemp evangelists, firm believers in the world-changing potential of this most versatile of plants, which can be used in everything from food to fabrics and building materials.

With permission from the Department of Primary Industries, they are in the first stages of a pilot project aimed at teaching farmers how to grow hemp and commercialise its myriad byproducts.

The Friars' crop, a mix of Chinese cultivars known as Yellow River and Lulu, is a fine example: the stalks can be used in the textile and construction industries - "they even use it, instead of steel, to reinforce concrete" - while the seeds can be eaten.

In December the couple applied to Food Standards for permission to sell the seed for human consumption, with approval expected early next year.

"They are a real superfood," Wendy says. "It's 23 per cent protein, and has more Omega 3 and Omega 6 than virtually any other source, including fish.

''In the early 1800s, Australia was twice saved from famine by eating virtually nothing but hemp seed for protein and hemp leaves for roughage."

But the couple also plan to become brokers for hemp products, importing seeds and matching overseas and local producers with those undertaking retail or construction projects.

"We want to kickstart consumer demand,'' Wendy explains. "It's hard, though, because hemp has for so long been vilified as a dangerous drug."

A film-maker, farmer, former horse trainer and grade rugby union player, Mr Friar has long been interested in permaculture and recycling; his company King Poo was one of the first to sell worm farms in the early 1990s. But it is hemp that has him raving.

"As a grandfather several times over, I am championing this now as the answer to a lot of our sustainability problems. We just have to lose the baggage we have about hemp, and approach it in a more mature way."