Viognier

Viognier came within a few hectares of extinction. In the late 1960s the total world planting was around fourteen hectares, all of it in Condrieu and Château-Grillet in the northern Rhône, and the grape survived by the stubbornness of a handful of growers.

Its revival was spectacular. Viognier is now planted across the Languedoc, California, Australia, South Africa and Argentina, and the reason is the aroma: apricot, peach, honeysuckle, orange blossom and a musky, almost tropical floral intensity that few white grapes can match.

It is technically demanding. Viognier develops its aromatics only in the last stages of ripening, so it must be picked late; but it loses acidity rapidly at the same time. The window between aromatic and flabby is narrow, and a picking decision a few days out in either direction produces either a neutral wine or an alcoholic, oily one. It is also a shy and unreliable cropper.

Condrieu, on terraced granite slopes above the Rhône, remains the reference: dry, full-bodied, powerful, with a rich oily texture and the apricot-and-blossom perfume at its most refined. The wines are expensive and should be drunk within a few years, since the aromatics fade.

In Côte-Rôtie, a small proportion — up to twenty per cent, though far less in practice — may be co-fermented with Syrah. Adding a white grape to a red sounds perverse and works: it stabilises colour and lifts the aromatics of the finished wine.

New World versions are frequently fatter and lower in acid, and oak tends to overwhelm it.

The narrow picking window is not an exaggeration. Viognier's aromatic precursors develop only in the final stage of ripening, and the acid falls away almost simultaneously, so the difference between a wine that smells of apricot and blossom and one that is heavy and flat can be four or five days in the vineyard.

It oxidises readily and has very little natural acidity to protect it, which is why most Viognier should be drunk within three or four years. A small number of Condrieu producers make wines that hold longer, usually with some barrel fermentation and lees ageing to build structure.

The grape's near-extinction and rapid global spread happened inside one lifetime, which makes it a useful case study. It also means a great deal of the Viognier planted worldwide is on unsuitable sites, chosen during the enthusiasm of the 1990s, and the average quality is correspondingly uneven.