Organic San Marzano Tomato Seeds - Lycopersicon lycopersicum

Organic Non-GMO Open-Pollinated San Marzano Tomato Seeds

Many world-class chefs consider San Marzano to be the finest paste tomato in the world, prized for its deep, balanced flavor and remarkable culinary versatility. The elongated red fruits have thick, meaty flesh, very few seeds, and low moisture content, making them ideal for creating rich tomato sauces, classic Italian marinara, salsas, and slow-cooked dishes. Their dense texture and concentrated flavor also make them excellent for roasting, fresh eating, and especially for canning and preserving, where they hold their structure and sweetness beautifully.

San Marzano plants produce vigorous indeterminate vines that continue growing and producing fruit throughout the season. The plants benefit from staking, trellising, or cages to support the heavy clusters of tomatoes. Fruits typically grow 4–5 inches long and develop their best flavor when allowed to fully ripen on the vine in warm summer sun. Tomatoes thrive in full sun and fertile, well-drained soil, and consistent watering encourages steady growth and productive harvests.

Harvest fruits when they turn a deep, vibrant red and feel firm yet slightly tender to the touch. Regular harvesting encourages plants to continue producing throughout the season. Use a sharp pruner or gently twist the fruit from the vine to avoid damaging the plant.

The story of the San Marzano is one of travel and transformation. Tomatoes are believed to have originated in Peru and were carried to Europe in the 16th century. By the 1700s, San Marzano found its home in the Kingdom of Naples, where it was first planted in the town of San Marzano sul Sarno. Grown in the mineral-rich volcanic soils at the foot of Mount Vesuvius, the tomato developed its signature flavor—sweet, complex, and deeply concentrated. This unique terroir, combined with generations of careful selection, shaped the tomato that has become synonymous with Italian cooking and remains a cornerstone of traditional cuisine today.

Today, San Marzano tomatoes continue to be treasured by gardeners, chefs, and home preservers alike, valued for their productive harvests, exceptional flavor, and unmatched performance in sauces and preserved foods.

Seed Profile

• Organic

• Heirloom 

• Open-Pollinated 

• Non-GMO

• Annual

• Exposure : Full Sun

• Indoors: 6-8 weeks before last frost

• Direct Sow: No 

• Seed Count: 25

• Days to Maturity: 80-90

• Plant Size: 5'-6'

Gardening Tips

Indeterminate.  Do not plant seeds too early, may become leggy and/or root bound. If necessary, use a row cover to protect from cold nights. Use stakes for support. 

Seeds should be planted indoors and kept in a dome with a heated mat for 4-8 weeks. 

It is key that your new starts be hardened off.  This is a process that requires taking them outside during the day, for a period of time, before they are planted. This acclimates your seedlings to the outside world, meaning the elements like the wind and sun. We do it for several weeks to a month as this strengthens their stems and overall plant structure. 

• Start for a short period of time initially, then graduate to more time each day
• One week minimum is recommended
• Bring them inside in the early evening and overnight
• Keep an eye on them and constantly water them. Make sure they have not blown over. 

Harvesting Tips

Harvest when fruits are fully red from shoulder to tip. San Marzanos don’t sweeten much after picking.  

Use sharp and clean shears rather than pulling; the plants can be brittle.  Avoid harvesting after heavy rain—excess water can dilute flavor and cause splitting.  Stress (warm days, moderate water) actually concentrates flavor—overwatering dulls it.

Regular harvesting encourages plants to continue producing throughout the season.