Guglielmo Winery is situated within the larger American Viticultural Areas (AVA) of the Central Coast and San Francisco Bay with the specific designation of Santa Clara Valley. Our vineyards are comprised of approximately 70 acres planted to Zinfandel, Petite Sirah, Merlot, Carignane, and Grignolino.

Our growing region is unique in that is a mixture of rural, urban, and suburban settings. The site is classified as Region II with regard to climate which is synonymous with some of the most famous appellations in the world. The soil type is classified as a Pleasanton Loam which is essentially a gravelly loam. This translates into a soil that is well drained and consequently well suited to grape cultivation. Climatic conditions are dominated by our costal influence from both the Monterey Bay in the Southwest to the San Francisco Bay in the North. Usually, fog hangs over the vineyard in the early morning, receding southward as the morning progresses. Damaging low temperature dips are well moderated by the costal influence that greatly minimizes the threat of frost damage.

In the vineyard, bud break occurs in mid-March with harvest beginning in early to mid-September. Vineyard practices are designed to be as sustainable as possible. Fruiting zones are kept open to facilitate light exposure and disease resistance. Reduced irrigation techniques are employed to encourage vines to express themselves fully. Crop load are also matched to accommodate these rigorous conditions.

Guglielmo Winery is the oldest, consistently operating, family owned winery in Santa Clara Valley. Most, if not all wineries in the Santa Clara Valley are either new or have changed ownership over the years. Guglielmo established the winery in 1925, has been continually in operation to present day, and owned by the same family. Few, if any can make that claim.