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Growing San Marzano Tomatoes – The Best Paste Tomato Around!

If you love making or want to make your own homemade salsa, pasta sauce, pizza sauce and more – then growing San Marzano tomatoes needs to be on your planting list for your next garden!

When it comes to making rich and flavorful sauces, the San Marzano tomato is hard to beat. Renowned for its incredible taste and meaty texture, this tomato variety has earned a top spot as the go-to tomato for both cooks and gardeners alike. 

The flavor of the San Marzano can be best described as slightly sweet with rich, hearty undertones. Because of its intense flavor and meaty interior, the tomato cooks down perfectly into a thicker sauce than most other tomato varieties will produce.

Growing San Marzano
The San Marzano is an all-star when it comes to making amazing pasta sauce – but is also perfect for creating homemade salsas that stand up well for canning.

Their elongated shape, thin skin, small seed core and exceptional balance of sweetness and acidity make them the ideal choice for home use.

Beyond its incredible taste, what really makes the San Marzano stand out is how productive it can be. It produces a large amount of fruit on its vines, while usually only growing to a total height of three to four feet.

Because of its more compact growing style, it is perfect for growing almost anywhere. It is great for traditional gardens and raised beds, but you can also grow it quite successfully in larger container gardens as well. It also requires far less support, staying upright with simple stakes or tomato cages with ease.

But perhaps best of all, this high producing plant also happens to be a determinate variety, so it will keep producing a large harvest of tomatoes right up until your first frost.

The History Of The San Marzano Tomato

San Marzano tomatoes originate from the Campania region of Italy. Grown in soil with a large percentage of volcanic dust from the notorious Mount Vesuvius, they became quite famous in Italy for being the go-to tomato for making sauce for the Neapolitan pizza.

ripe San Marzanos
San Marzano tomatoes ripen to a deep red. The almost non-existent seed core makes them perfect for salsa and sauce.

The tomato continued to soar in popularity in the late 1800’s in Europe, and it wasn’t long until it began to be shipped around the world. Of heirloom paste tomatoes, it is still today considered to be the gold standard for making sauce. See: Canning & Preserving Tomatoes

How To Grow San Marzano Tomatoes – The Best Paste Tomato Around!

Starting With Seeds Or Transplants

Because San Marzano tomatoes have become quite popular, you can often find local nurseries and greenhouses carrying the tomato as a transplant in the spring.

For those who grow their own plants from seed, there are plenty of options available for purchase. The key when buying seeds is to make sure you are purchasing true heirloom San Marzano seeds – and not a hybrid or offshoot of the original.

Look for reliable seed suppliers to ensure that you’re starting off with quality genetics. Quality seeds ensure you will be growing the characteristic flavor and texture these tomatoes are known for. Affiliate Seed Link: Italian San Marzano Paste Tomato Seeds, Heirloom Non-GMO, Indeterminate

growing san marzano tomatoes
San Marzano tomatoes grow in a quite compact form, making them ideal for any type of space.

Planting Tips – Growing San Marzano Tomatoes

Whether you’re starting your San Marzano tomatoes from seeds or transplants, timing is crucial. If starting from seed,  plant seeds indoors 45 to 60 days before the last frost date in your region. Begin hardening them off and transplant the seedlings outdoors once all threat of frost has passed.

If you’re using transplants, choose plants that are both healthy and sturdy. As with homegrown transplants, move them into the garden after any danger of frost has passed.

San Marzano tomato plants thrive on what nearly all tomato plans do – good soil, plenty of sunlight, consistent watering and plenty of space to grow.

When planting, plant transplants deep into the soil. This will allow the plant to grow extensive roots – not only to help anchor it well from the large load of fruit, but also to help bring in as many nutrients from the soil as possible.

Dig planting holes six to eight inches deep and mix in plenty of compost to the hole. Adding in a quarter cup of worm castings, coffee grounds and ground egg shells to the planting hole can help provide plenty of power early on.

egg shell powder
Adding crushed egg shells to your tomato planting hole can help prevent blossom end rot for tomato plants.
Allowing For Sunlight – Growing San Marzano Tomatoes

San Marzano tomatoes thrive on sunlight. With that in mind, choose a location that receives at least six to eight hours of direct sunlight daily. The more the better as sunlight helps fuel the plants growth and also its ability to ripen its fruit.

Although they only grow to three to four feet in height, the San Marzano is bushy. Allow two to three feet between plants to give them plenty of room to grow. This also allows for good air circulation, reducing the risk of disease and helping with pollination as well.

Once you have finished planting, mulch plants with a four to six inch layer of straw, shredded leaves or grass clippings. This aids in keeping competing weeds out and helps the soil conserve water for the plant’s roots.

Watering & Fertilizing – Growing San Marzano Tomatoes

San Marzano tomatoes need consistent and even watering throughout their growth cycle. On average, growing plants need 1 to 1.5 inches of rainfall each week. If that is not falling from the sky, then hand watering is a must. This is where mulch can be incredibly helpful in helping the soil from drying out too quickly.

When watering, water at the base of the plant. Always avoid overhead watering. Not only can it knock off blooms and forming fruit, it can also lead to mildew and other disease. Wet leaves often have trouble drying out, especially in humid conditions. The longer the leaves stay wet, the more likely issues will occur.

San Marzano’s require a fair amount of nutrients from the soil. Because of that, regular fertilizing can really help improve plant growth and yields. For best results, fertilize plants every 14 days with compost tea or an organic liquid fertilizer. Affiliate Link: Espoma Organic Grow! Liquid Concentrate Plant Food

Supporting Your Plants – Growing San Marzano Tomatoes

As San Marzano tomatoes mature, they produce heavy fruit clusters that can weigh down the branches. Provide sturdy support in the form of stakes or cages to keep the plants upright and prevent breakage. It is always best to put supports in place at the time of planting. This supports tomatoes early on – and helps prevent damage to the roots by driving them in later.

trellising vegetable plants
The San Marzano will develop large clusters of fruit on its vines. Pick ripening fruit often to help keep branches from becoming too heavy under the weight.

San Marzano tomatoes will benefit from light pruning to encourage airflow and reduce the risk of disease. A good rule of thumb is to prune the bottom 4-6” inches off the plant as it grows. This allows light and air to circulate throughout the plant more easily, helping with pollination and reducing the chance of disease.

Harvesting – Growing San Marzano Tomatoes

San Marzano tomatoes are typically ready to harvest two to three months after transplanting. Look for deep red coloration, firm texture, and a slightly sweet aroma. Gently twist or cut the tomatoes from the vine to avoid damaging the plant.

You can also pick early and have the tomatoes ripen off the vine. Once the tomato has blushed or slightly turned pink, it will continue to ripen off the plant. This can be helpful when the plant has a large amount of fruit on all at once.

Here is to growing San Marzano tomatoes in your garden this year. And even more, to experiencing the flavor of the best paste tomato around!

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