San Marzano

San Marzano fruit are often set beside the Roma tomato for comparison, sharing a plum shape but running thinner and more pointed, with thicker, meatier walls and fewer seeds. That flesh carries less juice than typical tomatoes, and the flavor leans more toward sweetness with less tartness than a typical tomato. The rosy red fruit can reach up to five inches long and set in thick clusters on the vine. The cultivar is rooted in the volcanic soil of Italy's Salerno province near Naples and was produced commercially throughout the 20th century.

San Marzano is one of only two tomatoes permitted by name in true Neapolitan pizza, a designation tied to its Italian origin. It is also recognized specifically as a canning tomato, valued for the flavor and quality it brings once processed rather than eaten fresh.

As a semi-determinate plant, San Marzano sets a heavy load of plum fruit into a comparatively compact footprint. In a 2018 summer trial it led other tomatoes on production and yield, and it has also performed well as a winter crop in mild coastal climates such as Southern California.

San Marzano tomatoes take their name from the town of San Marzano sul Sarno, near Naples in Italy's Salerno province, where they were first grown in volcanic soil in the shadow of Mount Vesuvius. One account holds that the original seed arrived in the Campania region in 1770 as a gift passed from Peru's colonial rulers to the Kingdom of Naples, taking root in that area. The variety was introduced commercially in 1926, becoming known locally as Pomodoro San Marzano dell'Agro Sarnese-Nocerino, and heirloom conservationist Amy Goldman Fowler has called it the most important industrial tomato of the 20th century, a reliable subject for canneries whose genes breeders drew on for decades. Its production today remains protected under a European protected designation of origin certification.