Concannon Vineyard in Livermore Valley is one of California’s quiet standard bearers. Founded in 1883 by Irish immigrant James Concannon, it became a home base for Petite Sirah, helping preserve and promote the grape through the 20th century when many others pulled it out. Farming centers on estate vineyards in Livermore’s warm days and cool maritime nights, ideal for ripening structured reds. Concannon famously propagated “Concannon clones,” especially for Cabernet Sauvignon and Petite Sirah, selections that spread statewide.² Winemaking leans traditional with stainless fermentation and measured oak aging to keep fruit and structure in balance.