John Geber likes to gamble. When he was operating the Tetley Tea operation in the United States, he introduced the now-famous round tea bag. When he was biking around Australia, he came across an abandoned chateau — and instantly bought it over the phone. This year he brought his mega-yacht to the East Coast to persuade wine consumers and merchants that Chateau Tanunda is not Yellow Tail.

Geber is as persuasive as he is charming — and so is his wine.

The Grand Barossa, an opulent 100-foot Azimut he bought last September, was docked at the Annapolis Yacht Club last week in one of 18 stops at ports along the East Coast. By the time we stepped aboard, the yacht's guest register had more than 700 signatures.

Geber was beaming. He argues that it cost him the same amount to bring 20 influential people to Australia for a week as it costs to run his yacht up and down the East Coast for several weeks. But, better, he can reach more consumers by bringing Australia to the United States.

"I'm either a fool or a genius," he ponders.

He has probably said that before. After the South African-born Geber left Tetley Tea, he launched several brands for the Australian Food & Beverage Group. A negociant, he often traveled to Barossa to buy grapes for his red wines. Suffering from jet lag one day in 1998, he took to his bike and came across an old, abandoned chateau in a small town called Tanunda.

Well, Chateau Tanunda wasn't just a chateau. Owned by Penfolds, it was the oldest wine building in Australia and once served as a classroom for young, aspiring winemakers — the likes of Max Schubert, the genius behind Penfold's Grange Hermitage, John Lehmann, Bill Seppelt and Grant Burge. Impulsively, he phoned John Duval at Penfolds, found out it was for sale, and bought it over the phone.

"Did I find it — or did it find me?" he wonders.

He spent millions restoring the 1890 building — "people told me I'd be bankrupt in a year," he says — but it's from here and the vast vineyards surrounding the chateau that he has launched a one-man crusade to improve Australia's wine image.

"Australia is a mess," he says. "We were first known for Yellowtail (immensely popular, cheap wine made by Casella Wines), then the critter wines and then the Molly Dookers."

In one sentence he has accurately summed up decades of an unwitting campaign to ruin a wine region's image. Now suffering from a glut of wine, Australia's export sales soared with introduction of Yellowtail. Then, winemakers hoping to jump on the bandwagon, introduced wines made in a garage with a cute Australian animal on the label. As if that wasn't enough, fruit bombs with high alcohol content — Marquis Philips, Molly Dooker, Clarendon Hills — won the acclaim of wine critic Robert Parker Jr. and suddenly became Australia's bellwether.

The wine region's fickle image had changed so many times, consumers finally got tired and moved on to Argentina, Chile, Spain and other countries whose image was better defined.

On a beautiful night cruising down the Severn River, Geber recites his story yet one more time. The 20 or so guests aboard sip his wines approvingly, perhaps influenced by the luxurious setting but hopefully recognizing the difference between Chateau Tanunda's wines and the plonk they've long associated with Australia.

In general, the wines are clean, crisp and authentic. A terrific 2012 Chateau Tanunda Grand Barossa Chardonnay ($12) was absent of the heavy oak flavors that once characterized Australia. A beautiful 2011 Chateau Tanunda Grand Barossa Shiraz ($14) had pure fruit character, a lingering finish and intense red berry fruit. A 2012 Chateau Tanunda Dry Riesling ($12) makes for a crisp aperitif on a summer day. The 2012 Chateau Tanunda Noble Baron Cabernet Sauvignon shows the power Barossa is able to produce.

Geber is able to strike a different course for several reasons. First, he sources his grapes from Australia's top region, the grapes are from very old vines, he uses oak sparingly, he softly crushes his grapes in basket presses to avoid harsh tannins, and he is not timid about blending grapes to achieve more aromas and length.

Not surprisingly, these wines are scoring top awards across Australia and the United States. You just won't find many better values. We highly recommend them for summer parties or just for yourselves.

Whether Geber's high-stake marketing gamble works will be seen in his sales. So far, he claims to have secured several big orders from his guests. We hope for Australia's sake that he sets off a trend that finally will stay.

As for the Grand Barossa, it left Annapolis for five more stops. When the trip is complete, Geber and his wife will return to Australia by plane and the yacht will be available for charter at $40,000 a week. Operators are standing by.