Understanding
Does the vintage matter?
Enormously in some places and almost not at all in others — and the honest version of that answer is more useful than a two-digit score, which is why you will not find one here.
A chart says “Bordeaux 2013: 78”. You are holding one bottle from one estate. Within any Bordeaux vintage the range between the best and worst wine made is far wider than the range between vintage averages — a grower who dropped fruit and picked selectively in a difficult year beats a complacent one in a celebrated year. The score compresses a distribution into a point and then invites you to apply that point to a specific bottle, which is precisely the inference it cannot support.
There is also a sourcing problem. Every vintage chart in circulation is a critic’s aggregated judgement. Reproducing one would be republishing somebody else’s opinion as fact, and producing our own would mean tasting thousands of wines. Inventing plausible numbers is not an option. So this page publishes what can be established instead: how much the vintage varies in a given place, and what the weather does when it happens.
What the weather actually does
Two corrections run through everything below, and both cost readers good bottles when they go unmade.
A difficult year usually means less wine, not worse wine. Frost, poor flowering and hail all reduce the crop, and the fruit that survives frequently ripens better for having less competition. The popular model — bad weather, bad wine — is wrong more often than it is right.
Heat is not simply good. Warm vintages get called great almost by reflex, because the wines are immediately impressive. Past about 35°C the vine stops photosynthesising, acidity is respired away and sugar keeps climbing, and what arrives is high in alcohol and short of anything to hold it together. The long, cool, unremarkable seasons produce most of the wines still being drunk with pleasure at thirty years.
Budburst, spring
Spring frost
A freeze after the buds have opened, which kills the young shoots carrying the year’s crop.
Once a bud has burst, the green tissue inside has no protection. Below roughly −2°C the water in the cells freezes and the shoot dies. The vine responds by pushing secondary buds, which are less fruitful and run a few weeks behind, so what survives ripens later and there is much less of it.
Effect on the wine
Often very little, in the bottle. The surviving fruit has a whole vine’s resources behind it and can ripen unusually well. The wine may be from a slightly later picking and show a little more concentration.
Effect on how much there is
Severe. A bad frost can remove most of a crop in a single night, and the loss cannot be made up later in the season.
What growers can do
Candles, wind machines, helicopters, and spraying water so that the latent heat of freezing holds the bud at 0°C. All are expensive, all are partial, and none of them work on a hard radiative frost across a whole valley.
Worth correcting. A frost year is a small year, not a bad one. The wine that gets made is frequently very good and there is simply less of it — which shows up as a price rise rather than a quality drop.
Flowering, early summer
Poor flowering (coulure and millerandage)
Cold, wet or windy weather during the two-week flowering window, which prevents the flowers setting into berries.
Vine flowers self-pollinate and need warm still conditions to do it. Cold or rain causes *coulure* — the flowers drop without setting — or *millerandage*, where berries set but never develop seeds and stay small and green. Both happen in a fortnight, months before anyone tastes anything, and both are entirely outside the grower’s control.
Effect on the wine
Millerandage in particular tends to concentrate: small seedless berries have a high skin-to-juice ratio, so the wine has more colour and tannin per litre. Some producers regard a mildly millerandé year as an advantage.
Effect on how much there is
Large reductions, and unevenly distributed — one variety may be hit while its neighbour in the next row is untouched. Merlot and Grenache are notably prone to coulure.
What growers can do
Nothing. Flowering weather is weather. Site selection and rootstock choice shift the odds slightly over decades.
Worth correcting. The commonest cause of a small vintage is not a dramatic frost or hailstorm but a fortnight of unremarkable cold rain in June that nobody outside the trade noticed.
Any point in the season
Hail
A localised storm that strips leaves and splits berries, sometimes destroying a specific vineyard while leaving the next village untouched.
Hail causes mechanical damage. Early in the season it removes leaves and shoots and the vine partly recovers; close to harvest it splits ripe berries, and split berries in warm humid weather rot within days. The damage is also a route in for bunch rot across the remaining fruit.
Effect on the wine
Where fruit is picked after hail damage, there is a risk of green, bitter or mouldy character from damaged berries. Careful sorting removes most of it, and sorting is what separates the estates that handle a hail year from those that do not.
Effect on how much there is
Potentially total for the affected parcels, and severe hail can damage the wood and reduce the following year’s crop as well.
What growers can do
Netting where the vineyard layout and appellation rules allow it. Cloud-seeding programmes operate in several regions and their effectiveness is genuinely contested rather than established.
Worth correcting. Hail is the reason a single appellation can have a fine vintage and a ruined one in the same year. Regional vintage generalisations are least reliable exactly where hail is common.
Harvest, autumn
Rain at harvest
The single most decisive weather event in wine, and largely a matter of luck.
Ripe berries absorb water through their roots and swell, which dilutes sugar, acid and flavour. Swollen berries split, and split berries in warm conditions develop grey rot within about forty-eight hours. Wet fruit also carries water into the press, and picking in mud compacts soil for years.
Effect on the wine
Dilution shows as a thinner wine with less concentration. Rot, where it takes hold, brings mustiness and can strip colour from reds through enzymatic activity.
Effect on how much there is
Usually modest directly, but severe once rot forces selective picking or discarding.
What growers can do
Pick before it arrives, at the cost of slightly under-ripe fruit, or wait it out and hope for drying wind. The decision has to be made from a forecast several days ahead and is the single hardest call in the year.
Worth correcting. Not all harvest rain is a disaster. A moderate rainfall on stressed vines during a drought year can restart ripening that had shut down entirely. Whether rain is bad depends on when it falls, how much, and what the weather does afterwards.
Ripening, summer
Heat spike during ripening
Sustained temperatures above roughly 35°C, at which the vine stops doing the thing you want it to do.
Photosynthesis slows sharply above about 35°C and effectively stops around 40°C. The vine closes its stomata to conserve water, so sugar accumulation halts while acid continues to be respired away. Direct sun on exposed bunches can scorch them outright.
Effect on the wine
High alcohol with low acidity — a wine that is simultaneously heavy and slack. Flavours shift from fresh fruit towards stewed, jammy or raisined character, and aromatic compounds in white varieties are degraded by heat.
Effect on how much there is
Berry dehydration reduces volume, and severe sunburn destroys affected bunches.
What growers can do
Leave more canopy for shade — a reversal of decades of leaf-removal advice — irrigate where permitted, and pick earlier. Longer-term responses include changing rootstock, row orientation and eventually variety.
Worth correcting. A hot vintage is not automatically a great one, though it is often reported as one. Past a certain point heat produces wines that are high in alcohol and short of anything to carry it.
Ripening, summer
Drought
A season with too little water, which is a problem — and mild water stress, which is not.
A vine under mild water stress stops putting energy into shoots and puts it into fruit, producing smaller berries with a higher skin-to-juice ratio. This is why the best vineyard sites are frequently the ones with the poorest water-holding capacity. Under severe stress the vine shuts down entirely, ripening stalls and the wine is left unbalanced.
Effect on the wine
Mild stress concentrates and is desirable. Severe stress leaves hard, green tannins and stalled sugar accumulation, and the wine tastes simultaneously unripe and alcoholic.
Effect on how much there is
Reduced berry size lowers yield, sometimes substantially.
What growers can do
Irrigate where it is legal, which varies enormously — much of the New World irrigates routinely and several European appellations forbid it outside emergencies. Cover crops, mulching and older deep-rooted vines all help.
Worth correcting. Water stress is one of the few cases where a difficulty genuinely improves the wine — up to a point, and the point matters. "The vine must struggle" is repeated far past where the evidence supports it.
Any point in the season
A wet, warm season
Humidity plus warmth is what fungal disease wants, and downy and powdery mildew can take a crop.
Downy mildew, powdery mildew and botrytis all establish in warm humid conditions. Left unchecked they destroy leaves — which the vine needs to ripen anything — and infect the fruit directly. A wet season is fundamentally a spraying season, and the number of passes needed can double.
Effect on the wine
Mildew taint carries into the wine as mushroomy, mouldy character. Powdery mildew on the fruit also raises the risk of off-flavours during fermentation.
Effect on how much there is
Can be severe, and organic and biodynamic growers are the most exposed because their permitted treatments are contact sprays that wash off in rain.
What growers can do
Spray, open the canopy to let air through, and in a bad year accept losses. This is the practical reason organic viticulture is harder in Bordeaux than in Mendoza, and it has nothing to do with conviction.
Ripening, summer
A long, cool, even season
The quiet condition that produces the wines people remember, and which almost never makes the news.
Aroma and flavour compounds develop over time, while sugar accumulates with heat. A long moderate ripening period lets flavour catch up with sugar, so the fruit reaches full flavour development at a sensible alcohol level with its acidity intact. A hot season reaches the sugar first.
Effect on the wine
Balance. Aromatic complexity at moderate alcohol, with acidity that gives the wine somewhere to go over time. Most of the vintages that are still being drunk with pleasure at thirty years came from seasons like this.
Effect on how much there is
Typically normal — this is an unremarkable year in volume terms.
What growers can do
Very little, which is the point. The main decision is holding one’s nerve and picking later than instinct suggests.
Worth correcting. The vintages that get called "great" at the time are frequently the hot ones, because the wines are immediately impressive. The cool even years often age better and are cheaper for years afterwards.
Harvest, autumn
Misty mornings and dry afternoons
The narrow condition that produces Sauternes, Tokaji and German Trockenbeerenauslese — and, if the afternoons stay damp, produces nothing.
Botrytis cinerea needs humidity to infect and dry conditions afterwards to concentrate rather than rot. Morning mist off a river followed by a sunny afternoon is the specific pattern. The fungus punctures the skin, water evaporates through the holes, and sugar, acid and flavour concentrate together. If the afternoons stay wet, the same fungus becomes grey rot and destroys the crop.
Effect on the wine
Concentrated sweet wine with a distinctive honeyed, marmalade character and — critically — acidity concentrated alongside the sugar, which is what stops it being cloying.
Effect on how much there is
Tiny. Yields for botrytised wine are a fraction of a dry wine’s, the fruit is picked over several passes berry by berry, and in some years the estates make none at all.
What growers can do
Wait, pick selectively, and accept that in some years there is no wine. Several Sauternes estates have declined to release a Grand Vin in difficult vintages.
Worth correcting. Noble rot and grey rot are the same organism. The difference is entirely the weather that follows the infection, which is why the great sweet-wine regions are all beside rivers that fog.
Where the vintage matters most
Derived from each place’s structured climate — latitude, maritime influence, rainfall timing, frost exposure — rather than from anyone’s judgement about particular years. It says how wide the spread between years is likely to be, not whether any given year was good.
Vintage matters enormously
A marginal climate where ripeness is not guaranteed and the weather at flowering and at harvest can decide the year. The difference between two consecutive vintages here can be larger than the difference between two producers.
What to do about it. Worth finding out what the year was like before buying in quantity — and worth remembering that a difficult year often produces smaller quantities of lighter wine rather than bad wine.
Anjou-Saumur · Bordeaux AOC · Cahors · Centre-Loire · Chablis · Chablis Grand Cru · Côte d’Or · Côte de Beaune · Hampshire · Haut-Médoc · Kent · Left Bank · Margaux · Mittelmosel · Montagne de Reims · Muscadet Sèvre et Maine · Nahe · Oregon · Pomerol · Saint-Émilion · Saint-Estèphe · Sancerre · Touraine · Vouvray · Willamette Valley
Vintage matters
Ripeness is usually achieved but not effortlessly, and rain or heat at the wrong moment leaves a clear mark on the wine.
What to do about it. Year-to-year differences are noticeable and worth knowing about, without being the first thing to consider. The producer still matters more.
Alto Adige · Barolo · Central Otago · Côte-Rôtie · Entre-Deux-Mers · Finger Lakes · Graves and Pessac-Léognan · Langhe · Niagara Peninsula · Pauillac · Pessac-Léognan · Pfalz · Rheinhessen · Ribera del Duero · Rioja Alta · Rueda · Sauternes · Tasmania · Wachau
Vintage matters somewhat
A dependable climate with occasional difficult years. Most vintages are broadly similar; the exceptions are the ones worth knowing about.
What to do about it. Buy on producer and style. Look up the vintage only if you are spending seriously or laying wine down.
Alsace AOC · Awatere Valley · Azores · Balaton · Barbaresco · Burgenland · Cafayate · Carneros · Casablanca Valley · Columbia Valley · Conegliano Valdobbiadene · Coonawarra · Cornas · Eola-Amity Hills · Franciacorta · Fruška Gora · Getariako Txakolina · Hawke’s Bay · Hemel-en-Aarde · Hermitage · Hunter Valley · Kakheti · Mendoza · Mornington Peninsula · Neusiedlersee · Okanagan Valley · Pouilly-Fuissé · Rhône Valley · San Antonio Valley · Slavonia · Sta. Rita Hills · Trentino-Alto Adige · Uco Valley · Valpolicella · Vaud · Vayots Dzor · Washington State · Yamanashi · Yarra Valley · Župa
Vintage matters little
Reliable sunshine, low disease pressure and — often — irrigation to smooth out what rainfall does not deliver. The grapes ripen every year.
What to do about it. Effectively ignore the vintage. Differences between producers, sites and picking decisions dwarf anything the weather did.
Adelaide Hills · Alentejo · Bandol · Bekaa Valley · Bolgheri · Brunello di Montalcino · California · Canelones · Châteauneuf-du-Pape · Chianti Classico · Clare Valley · Côtes de Provence · Crete · Dalmatia · Dão · Douro Superior · Etna · Gigondas · La Mancha · Limoux · Maipo Valley · Margaret River · McLaren Vale · Monção e Melgaço · Montalcino · Paso Robles · Pic Saint-Loup · Porto · Priorat · Rioja Oriental · Russian River Valley · Santa Barbara County · Sonoma County · Stags Leap District · Stellenbosch · Struma Valley · Swartland · Taurasi · Valais · Ventoux
What this measure does not cover
- Declared vintages are a different question. The Douro is hot and dry and scores as low-variation, which is true of ripeness and useless to somebody holding a Vintage Port. A declaration is a judgement that a year was exceptional, not that it was adequate. The same applies to vintage Champagne.
- Hail is local. One appellation can have a fine vintage and a ruined one in the same year, a village apart. Regional vintage generalisations are least reliable exactly where hail is common.
- Climate change is moving all of this. Places that were marginal fifty years ago now ripen reliably, and some reliably hot places have moved past the point where more heat helps. Assessments here describe the present, not a permanent state.
- The producer still matters more. In almost every region, the spread between growers within one vintage is wider than the spread between vintages.
How to find out about a specific year
Regional trade bodies publish harvest reports, and they are the best source available: they are written by people who were there, they describe conditions rather than scores, and they are free. They are also promotional, so read the weather and discount the adjectives. The growers’ own accounts of what they picked and when are better still.
Then apply it. A wet September in a place that scores high here means dilution and possible rot; a frost in April means a small crop and probably concentrated wine. That is a more useful chain of reasoning than a number, and you can check every step of it.
Related
- Will this wine age? — vintage variation is one reason bottle variation at twenty years is as large as it is.
- Regions — each place’s climate page carries the factors this assessment is derived from.
- Viticulture — what growers do about the weather, in more detail than fits here.