SproutSmart
SproutSmart Intelligent Garden Sowing

San Marzano

Tomato
Botanical illustration of San Marzano
🌱 75d to harvest Indeterminate

Sun-warmed and richly aromatic, San Marzano paste tomatoes ripen to a deep, velvety red with a firm, meaty interior and a pleasan…

Planting Schedule

Add San Marzano to your garden to build a schedule and get reminders.

Crop Dates

MilestoneDate
Start IndoorsMar 16th
Last FrostMay 4th
Transplant / Sow OutdoorsJun 29th
Harvest BeginsSep 12th
Harvest EndsOct 5th

Crop Details

TraitValue
Days to Maturity75
Sun RequirementsFull SunFull sun
Growth HabitIndeterminate
Support NeededStake
Planting DepthDeep
Germination Temp (°F)75
Min Soil Temp (°F)60
Min Night Temp (°F)50
Harden Off (days)10

Frequently Asked Questions


What pest or disease most commonly affects Solanum lycopersicum (San Marzano tomato), and how do I manage it?
Early blight and Septoria leaf spot are common on tomatoes, showing up as dark spots with yellowing on lower leaves. Remove and discard infected lower foliage, improve airflow with wider spacing and stake/tie plants upright, and water at the soil line to keep leaves dry. If the problem spreads, spray a labeled tomato fungicide early (start when spots first appear) and repeat according to the label interval.
How often should I water San Marzano tomatoes during the main growing phase?
During active flowering and fruit set, keep soil evenly moist by watering deeply about 1–2 times per week, aiming for consistent moisture rather than daily light watering. Water when the top 1 inch of soil feels dry, and apply enough to soak the root zone (roughly 6–12 inches). Mulch after plants are established to reduce swings in moisture that can trigger blossom-end rot and cracking.
How can I tell when San Marzano tomatoes are ready to harvest?
Harvest when fruits reach full red color (or deep red if grown for slightly firmer fruit) and feel firm but not hard—San Marzano should be elongated and heavy for its size. If you gently lift a ripe fruit, it should detach with minimal force from the vine. Plan harvests around day 75 from transplant (or roughly 70–80 days depending on conditions) and pick often to keep plants producing.
Botanical illustration of San Marzano

Sun-warmed and richly aromatic, San Marzano paste tomatoes ripen to a deep, velvety red with a firm, meaty interior and a pleasantly low-seed count. Their elongated, tapered shape holds its structure beautifully, delivering a dense, spoonable texture that’s ideal for thick sauces and slow-simmered favorites, as well as roasting for concentrated flavor. Grow these in cool-season confidence for a harvest that tastes unmistakably classic—bright, savory, and beautifully concentrated.

Sowing Tips

Transplant Conditions

Wait until soil reaches 60°F and nights stay above 50°F before moving outdoors. Harden off for 10 days first.

Expert Note

Start seeds indoors and transplant only once soil is consistently warm (60°F+) to prevent cold-stunting, then give plants steady watering for high-quality sauce fruit.