Semillon Gris: South Africa's Old-Vine Oddity

Growers in the Cape are nurturing this red mutation of the green Semillon Blanc grape. Malu Lambert investigates the unusual phenomenon, first identified in vineyards here back in the 1800s

- Malu Lambert

There’s something strange happening in South Africa’s Semillon vineyards. Green bunches turn red one year, then back to green the next. Hung like Christmas baubles on gnarled bush vines, the shapeshifting clusters are an enduring mystery.

Viticultural juggernaut and protector of old vines Rosa Kruger thought she was losing her mind when she first noticed this phenomenon, known as red Semillon or Semillon Gris.

‘I started marking the mutated [red] vines while taking cuttings for planting material,’ she explained when I asked her about the variety. ‘The following year the bunches on the vine would be green again. I thought I was making a mistake, but after a couple of years, I realised that Semillon Gris can actually mutate back to Blanc. In general, though, the Gris vineyards are fairly consistent once they’ve mutated.’

Semillon Gris seems only to occur in the Cape Winelands and appears to be an old-vine oddity. One of the Cape’s oldest varieties, Semillon was widely planted in the early 1800s. It was so ubiquitous it was simply called Groen Druif translated from Afrikaans as ‘green grape’.

These days, plantings of Semillon have fallen massively, though there are still pockets of heritage vineyards, some more than 100 years old, carefully guarded by viticulturists and winemakers.

In the early 1800s it’s said that 80% of the vines in South Africa were thought to be Semillon. By the mid-1800s, half of these had mutated into Semillon Gris.

Green and red