 The flesh is much thicker with fewer seeds, and the taste is stronger, sweeter and less acidic.The San Marzano vines are indeterminate and have a somewhat longer season than other paste tomato varieties, making them particularly suitable for warmer climates.As is typical of heirloom plants, San Marzano is an open-pollinated variety that breeds true from generation to generation, making seed saving practical for the home gardener or farmer.