Blending

Blending is not a compromise or a way of hiding faults, though it is often assumed to be. Most of the world’s greatest wines are blends: Champagne, Bordeaux, Châteauneuf-du-Pape, Port, Rioja.

Components may differ by variety, vineyard, vessel or vintage. In Bordeaux the blend is insurance against a maritime climate; in Champagne it is how house style survives vintage variation.

The decision is made by tasting, and it is one of the most skilled parts of winemaking.

Blending is the most underrated skill in winemaking and the least visible. Almost every wine is a blend of something — different varieties, different parcels, different barrels, different vintages — even when the label names a single grape.

Its original purpose was insurance. In a maritime climate like Bordeaux's, planting several varieties that flower and ripen at different times means a bad flowering or a wet September cannot destroy the whole crop. The blend is a response to risk before it is an aesthetic choice.

Its second purpose is completion. Cabernet Sauvignon gives structure and blackcurrant but can be hollow in the middle; Merlot fills it. Grenache gives fruit and alcohol but little colour; Syrah and Mourvèdre supply both.

Varietal labelling laws mean a wine sold as a single variety usually contains some of something else. The EU minimum is 85%, the US federal minimum 75%, and Oregon requires 90% — so "Cabernet Sauvignon" describes a majority rather than a totality almost everywhere.

Non-vintage blending, as in Champagne and Sherry, exists to produce a consistent house style year after year from vintages that vary considerably. That is a different objective from making the best possible wine in a given year, and both are legitimate.