San Marzano is considered by many to be the best variety to make sauce with in the world. The fruit is thinner and more pointed than that of the Roma tomato; and the low seed density in the fruits, meaty flesh and sweet flavour make this an ideal variety for making tomato sauce. Enjoy in salads with mozzarella, or use in stews.

Sow the san marzano tomato seeds about 1 cm deep into a tray or in small pots or cells, covered lightly, watered and placed at between 20 - 25 Celsius on a windowsill, heated greenhouse or propagator suitable for the heat loving seeds. Sow the tomato seeds in the UK for growing tomatoes outdoors late April to plant to final position in June, or February onwards if you have a greenhouse. Germination takes 10-16 days.

Tomatoes are always such a wonderful fruit to grow in the garden. No matter what you’re looking for, there are plenty of types and numerous varieties to choose from. One of our favourite tomato varieties at Seed Parade is the exquisite San Marzano. Today, let’s talk about where this lovely tomato variety comes from, its useful qualities, and how to care for it.

The Cultural Origin of The San Marzano Tomato Plant

Though tomatoes were first discovered in South America, they eventually became a beloved main staple in Italy. It didn’t take long for them to catch on throughout the rest of Europe thereafter. Originating in the Campania region of Italy, the San Marzano tomato gets its name from the small town in which it was developed.

The larger region where San Marzano tomatoes grow, the Sarnese Nocerino district (near Naples), is known for its unique and ideal growing conditions. This singular location, nestled at the foot of the infamous Mt. Vesuvius, is prized for its reliably perfect humidity, rich volcanic soil, and readily accessible water sources, many of which are natural springs and local wells.

In fact, the San Marzano tomato is so special that it has the prestigious DOP label (Denominazione di Origine Protetta), which in English translates to Protected Designation of Origin. It essentially means that the region in which these tomatoes are grown is protected, and tomatoes from this area are appropriately labelled as such. For this reason, tomatoes grown within the Sarnese Nocerino region are sold at a premium. Buyers from all over the world will often pay 3 to 4 times the price of what regular tomatoes sell for.

San Marzano tomatoes have a rich cultural history in Italy as well. They are the exclusive tomatoes used for making authentic Neapolitan pizza, a culinary tradition that dates back to the 1800s under the reign of the Queen of Savoy. The natural ingredients of this iconic pizza: handmade mozzarella, premium San Marzano tomatoes, and fresh basil, were chosen specifically to celebrate the colours of the Italian flag. Ever since artisanal baker Raffaele Esposito introduced the lovely San Marzano tomato to the Queen of Savoy, it has been famous ever since.

Culinary Applications for the San Marzano Tomato

This prized tomato has long been celebrated for its use in traditional Italian cooking, and it’s no surprise that fine dining restaurants and gourmet chefs around the world use imported San Marzano tomatoes in their cooking.

You too, can bring the San Marzano into your home kitchen to make to-die-for pizzas, mouthwatering pasta, gourmet sandwiches, and delicious charcuterie board ensembles. The San Marzano tomato pairs very well with mozzarella, garlic, olive oil, and basil. Then throw in a rosé or white wine to elevate your meal. Absolute perfection!

The San Marzano tomato boasts an impressive list of qualities. In appearance, these plum-sized, (70 to 100 grams) cordon-style tomatoes almost look like red-hot peppers. However, they are actually savoury sweet with a gentle disposition, mild acidity, and an unparallelled rich tomato flavour. On the outside, they have a deep red colour with a fine glossy finish. In shape, they are similar to Romas, except they have a longer and narrower body. They have a meaty, thick-walled, and firm interior.

Because they contain very little juice or seeds and peel easily, they have various culinary uses. They are the perfect candidates for canning, drying, roasting, and making thick pastes. Their pleasantly sweet and tangy flavour also makes them the preferred choice for making various types of pasta sauce.

Because they are low in acidity, these tomatoes may be a great choice for people who suffer from acid reflux or are otherwise sensitive to acidic foods.

How to Grow and Care for San Marzano Tomatoes

As we’ve learnt, importing authentic San Marzano tomatoes can be expensive. Therefore, growing your own tomatoes at home is the best way to ensure that you get to enjoy the freshest tomatoes available. Fortunately, we also have a temperate climate which enables us to grow this gorgeous tomato variety right here in the UK.

The San Marzano tomato plant is typically transplanted outside in April, but you may be able to start them even earlier if you’re also using a greenhouse. San Marzano seeds germinate within about 7 to 14 days and are ready for harvest after about 75 to 80 days. As an indeterminate (continuously fruiting) type you’ll be able to enjoy the fruit of San Marzano all summer long and into autumn. Also, be sure to store picked San Marzano tomatoes in a cool place in the kitchen and avoid refrigeration, as it diminishes their flavour.

Growth Habit

San Marzano tomatoes grow to be about 1 to 1.5 metres tall (3.3 to 4.9 feet) with a .5 to 1 metre spread (1.64 to 3.3 feet).

Spacing: Your San Marzano tomatoes need to be at least 60 to 90cm (25 to 36 inches) apart. Spacing is important because it helps tomatoes grow laterally instead of vertically. Adequate airflow and spacing will also help prevent disease. 

Transplanting: It should be noted that San Marzano tomatoes do not like their roots handled. For this reason, try to use larger planters for this variety if you’re starting your seeds early and intend to transplant them outside later. Also, be sure to harden off young seedlings before placing them outside.

Replicating the Ideal Growing Conditions

San Marzano tomatoes may take a little bit more maintenance than other tomato varieties, but they are well worth the investment. They are prolific producers and will benefit from a good support structure.

Sun Exposure: San Marzano tomatoes are avid sun lovers and need about 8 continuous hours of direct sunshine.

Temperature: In their native climate, San Marzano tomatoes enjoy coastal warm weather. Due to their close proximity to the coast, inbound sea air prevents them from drying out.

Additionally, they have a hardiness rating of H1c (USDA zone 11) where temperatures need to stay above 5° to 10° C (41° - 50° F). Ideally, they grow best when daytime temperatures are between 21° to 29° C (70° - 85°F) and overnight temperatures range from 16° to 21° C (60° - 70°F). Depending upon your specific area and local climate, using a greenhouse may be a good option.

Soil and Fertilising: San Marzano tomatoes need particular attention when it comes to the soil they are grown in. Since we are in the UK and don’t have easy access to volcanic ash, it’s recommended to substitute with wood ash. Also note that the best pH for your San Marzano tomatoes ranges between 5.8 and 7. You can use wood ash to raise the pH if needed. Similarly, adding more organic matter may lower the pH.

In general, tomatoes need compost-rich, loamy soil that drains well. For this variety, be sure to amend the soil so that it is rich in potassium, phosphorus, calcium, and magnesium.

Additionally, start to regularly feed your San Marzano tomatoes when the plant begins to set fruit. If fertilising your San Marzano tomatoes with a commercial type, use an NPK ratio of 5-10-10.

To learn more about the best soil composition for growing tomatoes, as well as how to control soil pH, read this informative article.

Watering: Your soil should have balanced moisture at all times and never be allowed to remain soggy. Conversely, if your San Marzano tomatoes dry out, they can become susceptible to blossom end rot. Also, be sure to water at the base of your plants and avoid splashing your tomato plant’s foliage, as this will help prevent the development of powdery mildew.

Additionally, it’s best to water your plants early in the morning and/or in the late evening. If the soil is moist, you can forgo watering at that time. It’s a good idea to check your tomato’s soil at least every 12 hours to assess its level of moisture. A layer of mulch will also help your soil retain consistent moisture.

Pruning

It’s best to remove the lower side shoots and leaves for this variety. Also remove suckers. Within a greenhouse, the San Marzano should have at least seven main trusses. For outdoor growing, it should have at least four.

Late in the season, remove the topmost central tip or stem of the plant once it has gained enough lower limbs. This will encourage the remaining fruits to ripen before cold weather sets in.

Common Diseases and Pests

San Marzano tomatoes need to be proactively protected from blight, blossom end rot, viruses, leaf mould, and magnesium deficiency. To prevent these diseases, be sure to grow your San Marzano in nutrient-dense soil and fertilise it regularly. It’s also worth noting that companion planting can help prevent many of these issues as well as discourage tomato moths and glasshouse whiteflies.

To prevent blossom end rot specifically, make sure your San Marzano tomatoes have enough access to calcium in the soil and that their roots are not disturbed. As mentioned before, be sure to water them consistently and don’t let them dry out. Also, keep hanging fruit from touching the soil.

Companion Planting with San Marzano Tomatoes

As the saying goes, “If it grows together, it goes together.” When buying San Marzano seeds, consider also buying seeds for these other notable plant companions. In doing so, you will reap a more abundant harvest and expand your access to fresh produce.

Basil, in particular, helps tomato roots expand. Its fragrance will smell amazing in your garden and mask the presence of tomatoes from opportunistic pests. Plus, basil improves the taste of tomatoes.

Garlic has anti-microbial, anti-viral, and anti-fungal properties for both humans and plants. As such, garlic protects your tomatoes from late blight and other soil-borne pathogens. Its pungent smell repels common pests as well. Like basil, garlic also helps improve the flavour of tomatoes.

Chives attract beneficial insect pollinators and help repel opportunistic pests.

To learn more about companion planting with tomatoes, read this detailed article.

These delicious artisanal tomatoes are a prized gem in the garden. They are rich in vitamins C and A, as well as other nutrients like potassium, folate, and dietary fibre. Plus, they are rich in antioxidants like lycopene that help prevent oxidative stress within the body.

Compounds present within tomatoes can also help the body produce more collagen. Collagen, in turn, helps us age more gracefully and retain great-looking skin. Therefore, the next time you’re enjoying a bright and juicy tomato, remember all the wonderful health benefits it is providing for your body!

We hope you’ll consider adding this delightful tomato variety to your home garden. Thanks so much for learning about San Marzano tomatoes with us today. Be sure to stop by often for the latest and most dependable gardening information.