Dr. Carole Meredith explains Petite Sirah:

1. The grape variety known as "Petite Sirah" in California is indeed the same as the French variety Durif.

They are simply two names for the same grape. We confirmed this around 1997, by comparing the DNA profile of California Petite Sirah with an authentic sample of Durif from the French national variety collection.

Some of the Petite Sirah vineyards in California are very old and, typical of old vineyards, contain some oddball vines of other varieties. Thus not 100 percent of the vines are always Petite Sirah, just as not 100 percent of the vines in an old Zinfandel vineyard are Zinfandel. There may be a few vines of other varieties mixed in; e.g., Carignane, Grenache, Barbera, Alicante, etc. This kind of "field blend" exists in most old vineyards all over the world, whether it's a Petite Sirah vineyard in California or a Grenache vineyard in southern France.

2. Petite Sirah is related to the true Syrah of the Rhone Valley.

Syrah is the father of Petite Sirah. Petite Sirah (aka Durif) arose as a seedling around 1880, in the experimental vineyard of Dr. Durif in southern France. The seed that became Durif was the result of a cross-pollination between an old French grape called Peloursin and Syrah. Thus Petite Sirah shares half of its DNA with Syrah. We discovered this in 1998, by using DNA paternity analysis methods just like those used with humans.

Carole Meredith
Professor Emerita Department of Viticulture and Enology
University of California