Almond Varietal Adaptation in Central Italy: Phenological, Ecophysiological and Agronomic Observations on Eight Cultivars of Commercial Interest

Almond cultivation in the Mediterranean basin is driven by Spanish production, which has combined innovation in cultivation techniques with research on varietal improvement, releasing self-compatible and late-flowering varieties that are better suited to areas prone to spring frosts. The growing demand for almonds has also influenced the Italian nut market, pushing growers towards almond cultivation even in areas that historically have no full vocation due to certain climatic constraints, such as cold winters and spring frosts, which are now less severe and less frequent as a result of climate changes, such as along the Latium coastline in Central Italy. In this new regional context, an almond collection orchard was set up in late 2017 in the rural environment of the municipality of Tarquinia (province of Viterbo) to test the local adaptation of commercial almond cultivars. Phenological observations and data acquisition were conducted for three consecutive growing seasons (2022–2024) and referred to eight cultivars introduced in the orchard: namely Genco, Guara, Lauranne Avijour, Penta, Soleta, Supernova, Tuono, and Vialfas. Each accession was monitored for phenological and ecophysiological traits, plant vigor and yield, yield efficiency, and nut and kernel traits. The trial proved that Lauranne, Penta, and Vialfas, due to their late flowering, were able to avoid possible damage from the spring cold recorded in 2023, while Supernova, Penta, and Genco, with an average yield over the three-year period of 2.51 ± 1.53, 2.44 ± 1.07 and 2.69 ± 1.42 kg plant−1, respectively, showed a higher average yield than the other cultivars tested.