San Marzano Tomato
Solanum lycopersicum
San Marzano is a paste-type tomato in the Solanum lycopersicum species. It needs full sun, warm weather and steady watering, and it is usually grown from seed started indoors.
Quick facts
- Germination time
- 6–12 days
- Germination temperature
- 24–32 °C75–90 °F
- Sowing depth
- 3 mm⅛ in
- Spacing between plants
- 46–61 cm1½–2 ft
- Days to maturity
- 65–90 days from transplanting
- Sun
- Full sun
Safety for cats and dogs: not yet verified.
By SeedBattle EditorsUpdated
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01 · Overview
About san marzano tomato
San Marzano is grouped with plum tomatoes in one extension listing, which describes it as indeterminate with no listed disease resistance. Tomatoes are warm-season plants that grow best at 70 to 80 °F (21 to 27 °C) during the day and 60 to 70 °F (16 to 21 °C) at night. Paste tomatoes have meaty interiors and few seeds and are preferred for drying, canning and sauces.
Growing details
- Start indoors
- 6–8 weeks before the last frost
- Sow outdoors
- Not yet verified
- Water
- Not yet verified
- Containers
- Yes
- Height
- 0.3–3 m1–10 ft
- Spread
- 0.3–1.2 m1–4 ft
- Frost tolerance
- Not yet verified
- Soil pH
- pH 5.8–6.8
- Life cycle
- Not yet verified
Sowing timeline
When to sow san marzano tomato seeds
Counted from your area's average last spring frost date. Find yours from a local weather service or garden center, then count back or forward.
- Germination time
- 6–12 days
- Germination temperature
- 24–32 °C75–90 °F
- Days to maturity
- 65–90 days from transplanting
02 · How to grow
How to grow san marzano tomato from seed
Start seeds indoors six to eight weeks before the last frost date in your area. Plant the seed about 1/8 inch (0.3 cm) deep, keep the mix moist but not wet, and expect seedlings in 6 to 12 days. Wait to set plants out until the chance of a last killing frost has passed and the soil is at least 50 °F (10 °C). Space plants 18 to 24 inches (46 to 61 cm) apart. Bury the lower part of leggy stems 2 to 3 inches (5 to 8 cm) deep and remove the lower leaves first to grow more roots. Containers should hold at least 5 gallons (19 L), with one plant per pot, while standard tomatoes may need 4 gallons (15 L).
03 · Care
Caring for san marzano tomato
Keep the soil consistently watered to avoid blossom end rot and splitting fruit. Too much nitrogen fertilizer leads to lots of leaves and little fruit. Use cages or stakes to keep the stems from breaking or drooping under the fruit. For plants staked to one to three main stems, remove the other suckers weekly.
At a glance
How san marzano tomato compares with other vegetables
Worked out from the growing facts of the 79 seeds in Vegetables on SeedBattle.
- San Marzano Tomato
- Each of the other vegetables
- Their average
- Germination timeAbout average
6–12 days
Average for vegetables: 10 days, from 39 other seeds
- Days to maturityAbout average
65–90 days from transplanting
Average for vegetables: 73 days, from 14 other seeds
- Germination temperatureWarmer than average
24–32 °C75–90 °F
Average for vegetables: 22 °C72 °F, from 38 other seeds
- Sowing depthShallower than average
3 mm⅛ in
Average for vegetables: 1 cm½ in, from 58 other seeds
- Spacing between plantsWider than average
46–61 cm1½–2 ft
Average for vegetables: 34 cm13 in, from 43 other seeds
- HeightTaller than average
0.3–3 m1–10 ft
Average for vegetables: 92 cm3 ft, from 57 other seeds
04 · Problems
Common san marzano tomato problems
Tomatoes are susceptible to pests such as stink bugs, tomato hornworms, aphids and cabbage loopers. Diseases include blossom end rot, verticillium wilt and fusarium wilt. Cultivars vary in disease resistance, so choose resistant types where you can. Uneven watering can cause fruit to crack.
05 · Harvest
Harvesting san marzano tomato
Harvest may begin 2 to 3 months after planting seed, or take up to 4 to 5 months depending on the variety. Pick fruit when the color begins to change.
06 · Storage
Storing san marzano tomato
Don’t refrigerate tomatoes; let them ripen fully indoors at room temperature. Green tomatoes can be stored at 50 to 70 °F (10 to 21 °C) for one to three weeks.
07 · Safety
San Marzano Tomato safety
Tomato is listed as a problem for cats and dogs. Leaves and stems are the parts of the plant listed as poisonous to people, and the fruit is the edible part.
San Marzano Tomato questions
How long do tomato seeds take to germinate?
Tomato seeds usually germinate in 6 to 12 days. Soil temperatures of 75 to 90 °F (24 to 32 °C) are best for germination.
When should I plant tomatoes outdoors?
Wait until the chance of a last killing frost has passed and the soil is at least 50 °F (10 °C). Start seeds indoors six to eight weeks before the last frost date.
Can I grow San Marzano tomatoes in a pot?
Containers should hold at least 5 gallons (19 L), with one plant per pot. Standard tomatoes may need a 4-gallon (15 L) pot at minimum.
How much sun do tomatoes need?
Tomatoes need full sun. Container plants need at least 6 hours of direct sunlight a day.
How many days until tomatoes are ready to harvest?
Tomatoes usually take 65 to 90 days from transplant to harvest.
Quick answers
More san marzano tomato questions
Short answers taken from the growing facts on this page.
How deep should I sow san marzano tomato seeds?
Sow them 3 mm⅛ in deep.
How far apart should I plant san marzano tomato?
Space the plants 46–61 cm1½–2 ft apart.
What temperature do san marzano tomato seeds need to sprout?
San marzano tomato seeds germinate at 24–32 °C75–90 °F.
How tall does san marzano tomato grow?
San marzano tomato grows 0.3–3 m1–10 ft tall.
What soil pH does san marzano tomato need?
Aim for soil at pH 5.8–6.8.
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