San Marzano Tomatoes: Tips For Growing San Marzano Tomato Plants

Red San Marzano Tomatoes
san marzano tomatoes
(Image credit: maxsol7)

Native to Italy, San Marzano tomatoes are distinctive tomatoes with an oblong shape and a pointed end. Somewhat similar to Roma tomatoes (they’re related), this tomato is bright red with thick skin and very few seeds. They grow in clusters of six to eight fruits.

Also known as San Marzano sauce tomatoes, the fruit is sweeter and less acidic than standard tomatoes. This provides a unique balance of sweetness and tartness. They are widely used in sauces, pastes, pizza, pasta, and other Italian cuisines. They are delicious for snacking as well.

Interested in growing San Marzano sauce tomatoes? Read on for helpful tips on tomato care.

San Marzano Tomato Care

Purchase a plant from a garden center or start your tomatoes from seed about eight weeks before the last average frost in your area. It’s a good idea to start early if you live in a short season climate, as these tomatoes require about 78 days to maturity.

Transplant San Marzano outdoors when the plants are about 6 inches (15 cm.) tall. Choose a spot where the plants will be exposed to at least six to eight hours of sunlight per day.

Ensure the soil is well-drained and never waterlogged. Before planting, dig a generous amount of compost or well-rotted manure into the soil. Dig a deep hole for each San Marzano tomato, then scratch a handful of blood meal into the bottom of the hole.

Plant the tomato with at least two-thirds of the stem buried underground, as planting tomatoes deeply will develop a stronger root system and a healthy, more resistant plant. You can even dig a trench and bury the plant sideways with the growing tip above the surface of the soil. Allow at least 30 to 48 inches (approximately 1 meter) between each plant.

Provide a stake or tomato cage for growing San Marzano, then tie up branches as the plant grows using garden twine or strips of pantyhose.

Water tomato plants moderately. Don’t allow the soil to become either soggy or bone dry. Tomatoes are heavy feeders. Side-dress the plants (sprinkle dry fertilizer next to or around the plant) when the fruit is about the size of a golf ball, then repeat every three weeks throughout the growing season. Water well.

Use a fertilizer with an N-P-K ratio of about 5-10-10. Avoid high nitrogen fertilizers that can produce lush plants with little or no fruit. Use a water-soluble fertilizer for tomatoes grown in containers.

Mary H. Dyer

A Credentialed Garden Writer, Mary H. Dyer was with Gardening Know How in the very beginning, publishing articles as early as 2007.