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Tomato Passport · plum · cordon

San Marzano

Low seed content, firm flesh, balanced sweetness and acidity — the classic cooking tomato.

Editorially reviewedLast reviewed 15/06/2026 · The Tomato Post Growing DeskPassport ref TP-SAN-MARZANO

At a glance

Cultivar
San Marzano
Also known as
San Marzano 2, SM
Botanical
Solanum lycopersicum
Origin
Campania, Italy
Fruit
Elongated plum, Deep red, 80–120 g
Flavour
Sweetness 6/10 · Acidity 6/10 — Meaty, few seeds, thick skin that slips easily after blanching.

Growing calendar

Sow

Feb · Mar

Plant

May · Jun

Harvest

Aug · Sept · Oct

Growing guidance

Difficulty
intermediate
Days to maturity
80 days
Height / spread
1.8–2.2 m / 50 cm
Indoor / outdoor
both
Greenhouse
excellent
Containers
acceptable — 40 L minimum per plant
Support
Sturdy cane; trusses become heavy when fruit sets.
Pruning
Cordon; remove side-shoots and lower leaves once fruiting begins.
Feeding
High-potash feed twice weekly under glass at peak season.
Watering
Even, deep watering. Avoid overhead watering to reduce foliar disease.
Disease resistance
Susceptible to blossom-end rot if calcium uptake is disrupted by dry spells.
Common problems
Blossom-end rot, late blight outdoors in wet summers.
Seed saving
Open-pollinated; seed saved from ripe fruit will come reasonably true.
In the kitchen
The definitive sauce tomato — peel, deseed, simmer with garlic and basil.

A note on weather and microclimate

Every plot is different. Regional weather, aspect, soil and glasshouse ventilation all affect timing and vigour. Treat these figures as a starting point, not a guarantee.

Current growers, kitchens and seed

Growers on record

None on record yet.

Currently served by

No kitchen on record this season.

Seed

  • Seed circles and swapsCommunity seed circles carry open-pollinated lines, often locally adapted. Provenance varies.

Sources

No external sources cited for this entry — content is original editorial and grower observation.