Grenache is a grape whose time has come" might be a line from a Marquez novel - reflecting as much the magical realism of wine as the idea that the great grapes wait to strut (and fret) their hour on the world's stage.

Until the second half of the 20th century the name of the variety which went into a wine was largely irrelevant - at least from the perspective of the consumer. Regular wine drinkers gravitated to an appellation - if they purchased the more bourgeois wines (Claret, Champagne, Port) - or to the colour and alcoholic strength (if they drank it alongside their baguette).

California changed all that as winemakers emulated the features they believed had helped to create the appeal of Old World wines, planting the most important French varieties from the best known regions. So it was the New World that gave the next generation of wine drinkers the cult of cultivar. What began as a fashion has acquired the force of religion in some markets, marginalising many widely planted varieties which have never enjoyed the same centre-stage status as cabernet or chardonnay.

It is easy to forget that, before this, with a few notable exceptions (chenin in SA, shiraz in Australia) cultivars were region-specific and therefore much less widely dispersed through the wine-producing world. In the mid-20th century there were only some 1000ha of chardonnay planted outside France. There was so little Cabernet planted in Australia that Max Schubert could not contemplate using it for Grange - and used the more plentiful shiraz instead.

It is hardly surprising that it took the Australian wine revolution - that 1980s-90s phenomenon which transformed Down Under from an object of ridicule for Monty Python to the biggest-selling origin in the UK - to change the status of shiraz. Almost unknown outside the Northern Rhone and Australia 20 years ago, shiraz is now the gout du jour across huge swathes of the wine world.

The thing about fashion is the imperative to change permanence is anathema, the dead rather than the quick. When it comes to what variety is a la mode, the next wave must begin its swell far out to sea even before the current darling - in this case the shiraz tsunami - breaks on the shore. This brings us to grenache.

The so-called Mediterranean varieties are powering past cabernet and pinot, in part driving the current success of shiraz. It is a safe prediction that the next star will match its flavour profile.

This makes the inevitable choice grenache. Widely planted around Southern France and Spain - and increasingly wherever Mediterranean climatic conditions prevail - grenache is the new black.

In SA, it is being planted at a feverish pace. At the same time the vinous avant -garde is tracking down ancient vineyards, mostly located in the increasingly fashionable West Coast appellations.

Many of the wines which overseas critics believe are our most interesting come from these sites and contain more than a sprinkling of fruit from those gnarled and weather- beaten vines.

Early in June the first international Grenache Symposium will be held in France, with Columella's Eben Sadie, L'Ormarins's viticulturist Rosa Kruger and me making up the South African contingent.

The event aims to enhance the prominence of grenache by ensuring an exchange of ideas between those who live by growing it, those who transform it into wine, those who write about what has been produced, and those who consume it.

Never before has there been so profound a focus on a single variety - certainly not on one which is already one of the most widely planted in the world of wine.

When, 10 years from now, grenache occupies the slot which once belonged to chardonnay and cabernet and currently is occupied by shiraz, it won't be necessary to wonder at how the change was wrought. All things - as Yeats wrote - hang like a drop of dew upon a blade of grass.

From Business Day 26 May 2010