One of California's oldest grape varietals, Zinfandel is not a native species, though it has become known as America’s quintessential grape. The exact origin of Zinfandel is a subject of academic debate with roots traced back to southern Italy and Eastern Europe. DNA testing in the early 1990s indicated that it is a cousin of the Primitivo grape with subsequent research leading scientists to Croatia, where DNA profiling links it to Crljenak.

Today, there are more than 32,000 acres of Zinfandel vines planted across California, making it one of the most popular grape varietals in the state, second only to Cabernet Sauvignon. Despite the abundance of Zinfandel, it is a challenging grape to grow due to uneven berry ripening.

High quality Zinfandel wines can be produced through careful viticultural techniques and the planting of Zinfandel in climates and soils particularly suited to it, Giarrusso’s vineyard in the Dry Creek valley being a perfect example.