Three decades ago, in a backyard garden in Western Australia’s Swan Valley, a mystery vine grew in secret. Its seed was likely carried by a bird or wind from a nearby Cabernet Sauvignon vineyard, located in a historic wine region 18 miles inland from capital city, Perth. Upon being discovered, its keepers dedicated a decade to covert propagation and experimentation before the vine was patented.
This is how Cygne Blanc, also known as White Cabernet and thought by many to be Australia’s first and only spontaneous indigenous wine grape variety, was born.
Cygne Blanc almost never existed at all. Unlike commercial vines, which are almost all direct clones of parent vines, seedlings that propagate naturally in the wild have the potential to grow into entirely new varieties. These plants are genetically distinct from their parents, though their fruit rarely possess the qualities needed to make good wine. Rogue seedling vines pop up in vineyards all the time, but are almost always ripped out.
However, fortune favored that lone Australian vine. It was discovered in 1989 by the garden’s steward, Sally Mann, who found it growing in patch of ochre-hued dirt. Sally is also the late wife of Dorham Mann, a third-generation winemaker and one of Western Australia’s most influential and important oenologists and viticulturists.
“My mother spotted a seedling vine in the garden by the house, not in the vineyard, and that’s actually what saved it,” says Anthea Mann, daughter of Dorham and Sally, and co-winemaker at Mann Winery.
Sally recognized the vine’s distinctive leaves were from the Cabernet family. But the type of grapes it would grow were a mystery. The likelihood that they would produce good wine was slim at best.
“We got a big surprise when [the vine] set fruit…everything in the vineyard started turning color and this thing stayed white,” says Anthea. “We knew then we had something that was a bit interesting. But the real fluke of the variety is that it turned out to be such a lovely wine grape. It has finesse and refinement like no other.”
Cygne Blanc is described as showing notes of rose petals, spiced apple and a silky texture comparable to Sémillon or Marsanne.
In order to obtain Plant Breeders’ Rights, Dorham Mann was forced to propagate in secret what Sally came to lovingly call “her” vine. In 1999, he applied to maintain the commercial rights to the variety, which the family dubbed Cygne Blanc, or “White Swan.” It’s a tribute both to their native Swan Valley and Cabernet’s French origins.
Cygne Blanc made its way off the Mann’s property just once. In 2001, the family granted an exclusive license to Port Robe Estate, in South Australia’s Limestone Coast, to plant some vines on their property and produce a dry, white table wine from it. The winery folded in 2009, and the vines were removed.
Today, a little more than one acre of the Mann’s nine-acre property is planted to Cygne Blanc. The gatekeepers of Australia’s only indigenous grape variety (defined as one grown from a seedling vine and not an Aussie-bred cross or hybrid) produce just 7,000 bottles of estate-grown, traditional-method sparkling wine. Of this, a third of the production is devoted to sparkling Cygne Blanc. Bottlings receive zero dosage, are aged 20 months on lees and released after a total of 2½ years. Mann says the resulting wine can age between 10–15 years.
The wines are all hand-picked, hand-disgorged and hand-labeled. The Manns open their modest tasting room each year on August 1 and shut the doors once the wines have sold out, usually eight or nine months later.
Whether Cygne Blanc will ever take hold again outside the Mann property remains unknown. But in a country that feels the effects of climate change, a native grape that’s born and bred in Australia’s climate and soil could be one solution.
“We have progressively built up an area of the vineyard dedicated to producing clean propagative material, so that we are in a position to involve the variety in an appropriate new project,” says Anthea.
For now, the Manns are content to craft their own unique wines from the clonal copies of the wayward grapevine found in Sally Mann’s garden more than 30 years ago.
Sally passed away in September 2018.
“Cygne Blanc is even more special to us now that we have lost her,” says Anthea. Sally leaves behind an important legacy, that of Australia’s sole native wine grape variety, her White Cabernet, tenderly nurtured by her family.
“We processed the 2020 Cygne Blanc fruit just over a week ago,” says Anthea. “At the moment, the winery is filled with the beautiful, perfumed scent of it happily fermenting.”