Giancarlos uncle, Sergio Tommasi, manages the viticulture at the estate. The five valleys of San Ambrogio, San Pietro in Cariano, Fumane, Marano and Negrar dominate the western, best and Classico-designated part of the region, and are often said to resemble the fingers of a hand. Tommasis vineyards are located in two of these valleys: Sant Ambrogio and San Pietro in Cariano. While they have a very traditional approach in the cellar, Tommasi is considered an innovator in the way they manage their vineyards. Tommasi was one of the first wineries to introduce the guyot method over the more traditional pergola system of vine-training, and their vineyards are planted at very high density, with resulting lower yields and fruit of increased complexity and concentration.Tommasi Viticoltori is one of the largest wine producers in the Veneto region, best known for its Amarone della Valpolicella Classico wines. It was founded in 1902 and is now run by multiple members of the fourth generation of the family. The company is based in Piedmont, in the heart of the Valpolicella Classico zone. It owns vineyards in some of the top sites such as La Groletta, Conca d'Oro and Ca'Florian, where it grows grapes for Valpolicella Classico Superiore, Ripasso, Recioto and Amarone wines. Elsewhere in the Veneto region, Bardolino wines are made at Tenuta Fossa Granara in Lago di Garda, and Lugana wines at Tenute San Martino. Tenute Le Volpare is the company's Soave estate on the prestigious Monte Foscarino. Tomassi also owns estates outside the Veneto: in Lombardy it owns the Oltrepò Pavese Tenura Caseo; in Tuscany the Montalcino estate Casisano (formerly Casisano Colombaio, purchased in 2015) and Poggio al Tufo in Maremma; and in Masseria, Puglia, Masseria Surani in Manduria, Puglia.
