Semillon: The Grape Behind Sauternes and Hunter Valley

Semillon is a golden-skinned grape used to make dry and sweet white wines, mostly in France and Australia, and it is its thin skin and its susceptibility to botrytis that make it dominate the sweet wine appellations of Sauternes and Barsac. The grape is native to Bordeaux, and it is still the region's most planted white: 54% of the white grape area by surface, against 36% for Sauvignon blanc and 7% for Muscadelle. In dry white Bordeaux it usually takes the smaller part of the blend. In the botrytised sweet wines of Sauternes, Barsac and Cérons it is often the dominant variety. Australia gave it a second home in the Hunter Valley, where it went by the name "Hunter River Riesling" for years. The wines are heavy and low in acid, and they last for decades. That last trait is the one that matters if you are holding bottles rather than opening them.

Where does Semillon come from?

Bordeaux. We give the grape as native to the Bordeaux region and puts its origin in the west of France,'s list of grape varieties likewise records France as its country of origin. It was known as Sémillon de Saint-Émilion in 1736, and the modern name resembles the local pronunciation of that town's name. Its berry skin is classed as blanc and it carries VIVC number 11480.

The two hazards on its record are sunburn and Botrytis cinerea. That pairing is the grape's whole career in one line: the fungus that would be a fault on almost any other variety is the reason its most valuable wines exist at all.

Where is Semillon grown today?

France and Australia carry the wines you would cellar, but Chile is reputed to have the largest plantings of the grape, although the number of acres planted fluctuates often. The spread is wide and thin outside a few strongholds.

Country or region	What Semillon does there
Bordeaux	54% of the white grape area; blended with Sauvignon blanc and Muscadelle for dry Bordeaux blanc, and often dominant in the sweet wines of Sauternes, Barsac and Cérons
Hunter Valley, Australia	Long called Hunter River Riesling; four distinct styles, two of them considered unique to Australia
Chile	Reputed largest plantings of the grape, on an acreage that moves year to year
South Africa	1% of Cape vines today, against more than 90% of plantings in the first half of the 19th century
Washington State	Varietal bottlings since the early 1980s, plus Ice Wine and Late Harvest wines
California	Planted primarily to blend with Sauvignon blanc

Beyond the Hunter, the grape is finding favour with Australian producers in the Barossa Valley and Margaret River, and the Adelaide Hills is becoming a flourishing region for it, with the cooler climate producing wines of great complexity. Elsewhere it is scattered: at least one Idaho winery makes a varietal bottling, at least four Texas vineyards grow it, and there are plantings in Argentina, Canada's Niagara and British Columbia, and more recently New Zealand.

What styles does Semillon make?

Dry and sweet in France, and four separate styles in the Hunter Valley alone.

In France the grape is grown mostly in Bordeaux, blended with Sauvignon blanc and Muscadelle. When dry, the wine is called Bordeaux blanc and is permitted in Pessac-Léognan, Graves, Entre-Deux-Mers and other less-renowned appellations, and in that form Semillon is generally a minor constituent in the blend. We put the typical white Bordeaux blend at 80% Semillon and 20% Sauvignon blanc, while noting that the dry whites specifically are often 100% Sauvignon blanc or a blend dominated by Sauvignon blanc with Semillon. Read the two together and the lesson is practical: the grape's share swings by style, so check whether the bottle is dry or sweet before you assume what is in it. Graves is the only Bordeaux subregion with a classification for dry white wines, and the better versions tend to carry a significant oak influence.

The sweet wines are where Semillon leads. In Sauternes, Barsac and Cérons the vine is exposed to the "noble rot" of Botrytis cinerea, which consumes the water content of the fruit and concentrates the sugar in its pulp. The grapes shrivel, and acid and sugar levels are intensified. That is the whole mechanism, and it only works on a grape thin-skinned enough to let the fungus in. Our guide to how sweet wine is made covers the process in more detail, and the dessert wine guide covers the category around it.

Australia's four Semillon styles, are a commercial style often blended with Chardonnay or Sauvignon blanc; a sweet style, after that of Sauternes; "a complex, minerally, early picked style which has great longevity"; and an equally high quality dry style, released soon after vintage as a vat-aged or bottle-aged example. The last two were pioneered by Lindemans, Tulloch, McWilliam's Elizabeth, Drayton's and Tyrrell's, and are considered unique to Australia.

How does Semillon behave in the vineyard?

It is relatively easy to cultivate and it crops hard: six to eight tons of grapes per acre, consistently, from vigorous vines. It is fairly resistant to disease, except for rot. It ripens early, and in warmer climates it takes on a pinkish hue as it does. The thin skin that lets botrytis in also puts the fruit at risk of sunburn in hotter climates, which is why the grape is best suited to areas with "sunny days and cool nights".

Yield is where the two records pull apart, and it is worth knowing which one you are reading. We say the grape has a high yield. We call it the lower yielding of the two main Bordeaux whites, with Sauvignon blanc now grown in an area more than half the size of Semillon's. The second is a comparison against Sauvignon blanc in one region, not an absolute.

How long does Semillon age?

A long time, and the Hunter Valley is the proof. Semillon wines are "rather heavy, with low acidity and an almost oily texture", and wines based on the grape can age a long time.

Most bottle-aged Hunter Semillons show "a buttercup-yellow colour, burnt toast or honey characteristics on the nose", along with complex flavours on the palate, a long finish and soft acid. Young Hunter Valley Semillon is almost always dry, usually showing citrus flavours of lemon, lime or green apple. Cooler-year Hunters seem to be the most highly sought after, and some of the 1974 and 1977 vintages are still drinking well. A dry white from the mid-1970s that is still drinking well is the strongest argument there is for treating a Semillon holding as a cellar position rather than a drink-soon one. Track yours against its own appellation and vintage on our drink-now maturity tracker.

Why has Semillon lost ground?

Because the fashion moved and the grape did not. Semillon was once considered the most planted grape in the world, and that is no longer the case. In the 1950s it made up over 75% of Chile's vineyards. By the 1820s it covered over 90% of South Africa's vineyards; today it accounts for just 1% of South African Cape vines. In Bordeaux it was the most planted grape in the region in the late 1960s and has been in constant decline since, though it remains the most common of Bordeaux's white grapes. Sauvignon blanc went the other way, overtaking Ugni blanc as the second most planted white Bordeaux grape in the late 1980s. If you want the other half of that story, read our guide to Sauvignon blanc.

Outside its strongholds the grape is "unpopular and often criticised for lack of complexity and intensity", and plantings have decreased over the last century. The decline has a second-order effect that Bordeaux took seriously: falling popularity means fewer clones cultivated in nurseries, and producers have projected a future shortage of quality wine as a result. In 2008, 17 Bordeaux producers, among them Château d'Yquem, Château Olivier, Château Suduiraut and Château La Tour Blanche, formed an association to grow their own clones.

What else is Semillon called?

Six names beyond its own, and two of them carry the history.

Synonym	Where it comes from
Wyndruif	South Africa, meaning "wine grape", from the era when the variety covered over 90% of the country's vineyards
Groendruif	South Africa, translating as "Green grape", a Cape heritage name with origins as early as the 17th century
Hunter River Riesling	Australia's Hunter Valley, used for the variety there for a long time
Blanc doux	Also a name for the red grape Blaufränkisch, so read it in context
Colombier	Recorded synonym
Malaga	Recorded synonym

Two further naming traps are worth knowing. Early in Australia's viticultural development, the country's most significant white variety was Semillon mislabeled as Riesling. And Semillon Rouge is not a Semillon at all: it is a synonym for Merlot, though a genuine red mutation of Semillon does exist and was once quite common in South Africa.

What does this mean for your bottles?

Start with the appellation, not the grape. The label will not name the variety: Bordeaux labels generally carry the estate, its classification, the appellation, whether the wine was château-bottled or assembled by a négociant, the vintage and the alcohol content. Where the classification does the heavy lifting is Sauternes. The sweet white wines of Sauternes and Barsac were ranked into three categories under the 1855 classification, with only Château d'Yquem classified as a superior first growth, and our 1855 classification guide sets out the tiers. The neighbouring sweet appellations on both sides of the Garonne, Loupiac, Cadillac and Sainte Croix du Mont, make similar wines but fall outside a classification that covers only the red wines of the Médoc and the sweet wines of Sauternes and Barsac.

Liquidity is on your side either way. Because of the combination of longevity, fairly large production and an established reputation, Bordeaux wines tend to be the most common wines at wine auctions. See where the classified names are trading on our market index, and where the estates sit on the Sauternes map.

Holding Semillon is a patience decision, and a mid-1970s Hunter still drinking well is the reason patience pays here. Get drink-window data for your cellar and watch each bottle against its own appellation and vintage instead of guessing at the year.