San Marzano tomatoes are famous worldwide for their sweet taste and thick flesh. Their reputation is a gold standard by which other tomatoes are judged.
They are a high yielding tomato variety with origins dating back to 18th century Italy.
San Marzanos are not a commonly grown cultivar and there’s a low probability of finding starters, which is why your best option is to start growing them from seed.
Here are some facts you might not know about this wonderful tomato variety.
What Is So Special About San Marzano Tomatoes?
A pizzaiolo worth his salt knows that the key to a great pie is found in the right sauce.
The best sauce is a little sweet with a tangy taste. This is what San Marzano tomatoes offer. So what really makes them so special?
Near Naples, in the Campania region of Italy, these tomatoes are grown in the shadow of Mount Vesuvius. They’re grown in rich volcanic soil which gives them low acidity and a sweet flavor.
A stable climate, sunny weather, and proximity to the Mediterranean work together to make these tomatoes great for any garden.
Because San Marzano plants are delicate, the tomatoes are handpicked immediately when they ripen. Their high quality makes them an all-time favorite to use in cooking.
Are San Marzano Tomatoes the Same as Roma Tomatoes?
Even though they are related and similar in appearance, there’s more than one way to spot the difference.
San Marzanos are plum tomatoes, but thinner and more pointed than Roma tomatoes. Their walls are thicker and lined with fewer seeds. This accounts for their low acidity and makes them a sweeter variety.
They have a thick skin that is easy to peel and when ripe, they are a deep red color. San Marzano tomatoes have a low seed count compared to other plum tomatoes. This type usually has 2 seed pockets, whereas the regular variety has four or five.
Once San Marzano tomato seeds are sown, it takes 75 to 80 days for the fruits to ripen and be ready to dress and serve. Starting your tomatoes from seed should be done close to 8 weeks before the last average frost in your area.
These Italian tomatoes are available from the start of August to the end of September.
Are Some San Marzano Tomatoes Fake?
Some San Marzano tomatoes have been the subject of fakeries, like olive oil or honey. Official San Marzano canned tomatoes are sold cut in half or peeled whole. Genuine San Marzano canned tomatoes bear a Pomodoro San Marzano dell’Agro Sarnese Nocerino D.O.P label.
Bonafide canned San Marzano tomatoes from Italy are consistent in their deep red color, vibrant taste, and firm flesh. Harvesting is done when the tomatoes are perfectly ripe.
Knowing where the Italian canned tomatoes actually come from instead of where they were distributed is important.
How to Grow San Marzano Tomatoes
Italian San Marzano tomatoes have been grown for hundreds of years and it’s easy to see why. The plants grow to a manageable height of 5 to 6 feet and produce a bountiful harvest.
The tomatoes are perfect for gardeners looking to make the most of a patio or small space.
To maximize your small space, go for a determinate San Marzano plant as they are hybrids that produce bushier, shorter plants.
For example, you can enjoy a harvest from a golden San Marzano hybrid which grows to be 3 feet tall and is perfect for any container garden.
The only drawback is that this type may not produce a large harvest compared to the intermediate variety, as the plants are smaller.
They are best grown in plant hardiness zones 5 through 10 of the U.S. Department of Agriculture.
To grow San Marzano tomatoes in your home, here’s what you need to know:
Start From Seeds
San Marzano plants can be bought from gardens centers, but you gain a lot more by growing your own!
We recommend starting out with the hybrid San Marzano type as it gives you a bigger harvest and takes less time to ripen. You can later switch to a heritage type tomato if you prefer.
You can easily keep track of your tomato plant, recording the age as well as how and where it was grown.
This allows you to maximize your yields as you are invested in proper seedling care and timing. The seeds should be planted indoors for 6 to 8 weeks before the last spring frost.
Remember: tomatoes need close to 6-8 hours of direct sunlight daily. The San Marzano variety is no different.
Containers and Cages
When it comes to tomatoes, San Marzano can be grown in containers and transplanted later. Make sure to use a large container – a 20-gallon one will do.
These plants grow with great vigor and their root system is proof of that. A small container will decrease your yield by causing the roots to cramp.
Even though this type of plant doesn’t grow to be as large as other varieties, they need the support of a cage. A tomato cage will help the plant grow upwards and support the fruiting branches.
Without one, your harvest can be ruined if the tomatoes droop, become overcrowded or form on the ground. Your plant could also break under its own weight. Find a tomato cage` that is at least 5 feet tall – this provides the best results.
Water Requirements
It’s vital not to overwater your San Marzano tomatoes. A great idea is to evaluate the top-most layer of the soil in the pot. If the texture is a little grainy and dry, slowly sprinkle some water onto it.
Using a sprinkler on these special Italian plants or applying a dripping system is the best way to go. Watering cans with a large opening can ruin the plant by washing the soil away.
Fertile, Well Draining Soil
To match up to the rich volcanic soil of Italy, place your seeds in soil that is full of nutrients and moisture.
If your tomato plant is in a container, make sure you use high-quality potting soil; if they are in-ground, then add aged manure or compost for more organic nutrients. This is done because Marzano tomatoes are heavy feeders.
Ensure that the soil drains well in either case. The roots of plants in slow-draining soil can be smothered and cause rot.
Note: If you choose to transplant your tomato outside, the fruit will ripen within 70-80 days. When ripe, grown tomatoes will stay fresh for 2 to 3 days if stored at room temperature.
Sliced or cooked Italian Marzano tomatoes should be kept in a sealed container in the refrigerator for up to a week.
Learn More About Home Gardening
Find out more about growing tomatoes from the Gardening Channel.
With our vast range of articles, you’re sure to find the information you’re looking for to excel in your home gardening.
Here are a few great articles to get you started:
- Sauce tomatoes: hearty varieties
- How many tomatoes do you get from one plant?
- Tomato season: the perfect time of year to grow your tomatoes
- 153 best ways to use the tomatoes you grow in your garden
Photo from Flickr by Forest and Kim Starr
my san marzano sseem small and around only one ounce