Plum Tomatoes: How to Grow Plum Tomatoes in Gardens and Containers

Plum tomatoes are the secret to an amazing homemade tomato sauce! The oval-shaped fruits have a sweet-acid flavor and meaty texture which cooks down into a thick, rich sauce. Plus the plants are easy to grow in garden beds and containers. When given sunshine, fertile soil, and consistent moisture you can expect a bumper crop of plum tomatoes for summer sauces. Read on to learn more about planting, growing, and harvesting plum tomatoes.

Roma tomato plant — Plum tomatoes are the classic tomato for sauces and paste. The fruits have a low water content and a sweet-acid flavor and cook down into a rich, thick sauce.

What are plum tomatoes?

There are many types of tomatoes you can plant in your garden or in pots. Plum tomatoes are the classic tomatoes used for making sauces, juice, and tomato paste. They’re also called processing or paste tomatoes and have oblong fruits often with blunt or pointed ends. Plum tomatoes are essential in tomato sauce because they have less liquid than slicing types of tomatoes. The fruits have thick walls and are often described as ‘meaty’, a nod to their density and low water content. They also have fewer seeds than slicers which is another bonus for sauce makers.

Plum tomatoes are typically grown for sauces, but you can also enjoy the fruits fresh in salads, sandwiches, and salsa. I grow a handful of plum tomatoes in my raised garden beds, fabric planters, and deck containers each summer. Some varieties have determinate growth while others are indeterminate and require sturdy staking. Most plum tomatoes have red fruits but some, like Sunrise Sauce and Banana Legs, have golden and yellow fruits.

tomato plant in a garden — There are many varieties of plum tomatoes to grow. Some have determinate growth and others have indeterminate growth. Stake the plants well to keep them upright and off the ground.

Growing plum tomatoes

Plant seeds for plum tomatoes indoors six to eight weeks before the last expected spring frost. I like to sow tomato seeds in cell packs and trays, planting in a high-quality seed starting mix. Place the containers under grow lights or in a sunny window. As the seedlings grow, keep the soil lightly moist and fertilize every 10 to 14 days with a diluted liquid organic fertilizer.

About a week before transplanting, start the hardening off process by placing the seedlings in a shady spot outdoors. Over the next four to five days gradually introduce the plants to increasing levels of light. After a week they should be ready to be moved to the garden or containers.

Planting plum tomatoes

Tomatoes are a heat-loving crop and need eight to ten hours direct sun each day. They also appreciate fertile, well-draining soil so amend with compost or aged manure before planting. I also like to work a granular organic vegetable fertilizer into the soil.

When setting the transplants in the ground, plant them deeply to encourage deep-rooted plants. I bury the bottom two-thirds of the stem and remove any leaves that would be under the soil. Deep planting promotes a robust root system and plants that are less susceptible to drought stress. Get more tomato growing secrets in this detailed article.

Planting a tomato seedling — When transplanting plum tomato seedlings plant them deeply. The plants form adventitious roots all along their stem for a more robust root system.

Growing plum tomatoes in containers

Plum tomatoes can also be planted in pots, planters, and fabric beds. If you want to grow them in containers select determinate varieties like Sunrise Sauce or Roma VF that only grow about 4 feet tall. Once you’ve picked your pots – and remember that bigger is better as large pots don’t dry out as quickly as small containers – add the growing medium.

My go-to growing medium for container tomatoes is two-thirds high-quality potting mix and one-third compost or aged manure. I also add a couple of tablespoons of a slow release organic vegetable fertilizer to the pot which provides a steady release of nutrients.

As the plants grow, it’s essential to water pots often; don’t allow them to dry out to the point of wilting as that can encourage blossom end rot. To learn more about blossom end rot and how to avoid it, check out this awesome article by Jessica. Self-watering pots can also be DIY’d or bought to help you stay on top of watering. You want the soil to be lightly moist. If you’re not sure whether you should water, stick your finger about two inches into the growing medium. If it’s dry, water. I water my potted tomatoes daily in summer, but on really hot days I water in the morning and evening.

growing Roma tomatoes in containers — Plum tomatoes can be grown in pots or garden beds. If planting in containers choose a large pot with drainage holes and fill with a mixture of potting mix and compost.

Staking and supporting plum tomatoes

Once my tomatoes have been transplanted into my raised beds or containers, it’s time to consider staking. There are many options for supporting tomato plants; cages, stakes, trellises, or even techniques like the Florida weave. Let’s take a closer look at the most popular ways to support tomato plants:

Cages – I use tomato cages in my garden… but I use them for peppers and eggplants, not tomatoes. That’s because standard tomato cages are rarely strong enough to support vigorous tomato plants. You can use them for determinate varieties but I prefer the tall, heavy-duty tomato cages you can buy from various suppliers.
Stakes – My favorite way to support tomato plants is to stake them. I buy 1 by 2 inch by 8 foot pieces of untreated lumber and cut off the bottom couple of inches at an angle so they’re easy to push into the soil. As the plants grow I tie the new growth to the stake every week with garden twine.
Trellis – I use 4 by 8 foot wire mesh panels to make trellises and tunnels in my garden. They can also be used to support tomato plants with an 8 foot long panel supporting six tomato plants. You need to tie the new growth to the trellis every week in summer but the wire makes a very sturdy support for indeterminate plum tomatoes like Amish Paste and Big Mama.

plum tomato plant in container — Pozzano is one of my favorite plum tomato varieties to grow. The plants are vigorous and productive and the bright red fruits make a sublime sauce.

Care and maintenance

Tomatoes are a long season vegetable that remain in the garden all summer long. To promote healthy plants and large harvests it’s important to provide the plants with regular water and nutrients.

Watering – As noted above, it’s very important to water plum tomato plants consistently. It’s also a good idea to water the soil and not the plant. Splashing water, especially late in the day when plants don’t have a chance to dry off before night, can spread soil borne diseases. I use a long-handled watering wand to direct water to the base of the plant. It’s quick and easy! I also water in the morning if I can. That way any water that may have splashed on the foliage has time to dry before nightfall.
Fertilizing – I feed my plum tomato plants with a liquid organic fish or kelp fertilizer every two to three weeks throughout the growing season.

When to harvest plum tomatoes

When picked at the peak of ripeness a plum tomato is a garden treat! The fruits are firm but have a little give. They’ll also have turned the mature color indicated on the seed packet. Tomatoes ripen from the inside out so color and feel are good indicators of whether your plum tomatoes are ready to harvest. Ripe tomatoes also come off the stems with a gentle tug. If you try to harvest them and the fruits still firmly attached, they’re not ready to be picked. That said, I prefer to use garden snips to harvest my plum tomatoes. Trying to pull the ripe fruits from the plant can damage the cluster and knock off still-green tomatoes.

The fruits of determinate varieties ripen around the same time. Indeterminate varieties produce a steady crop of tomatoes until frost. If you want to make a big batch of sauce at one time, grow determinate varieties as the fruits ripen together. Because I like to make small batches of sauce all summer long I prefer indeterminate plum tomatoes and harvest as the tomato clusters ripen.

harvesting plum tomatoes — Harvest plum tomatoes when the fruits have reached their mature color and are firm but with a little give.

Plum tomatoes vs roma

The terms ‘plum tomatoes’ and ‘Roma’ have become almost interchangeable but are they the same thing? Yes and no. Roma tomatoes are a variety of plum tomatoes grown by gardeners to can or make sauces. Roma tomatoes are a standout variety of plum tomatoes, but there are many other varieties you may want to plant. Check out my favorites in the list below.

8 varieties to grow in your garden

There are many varieties of plum tomatoes available through seed catalogs. When selecting which ones to grow, be sure to read the variety descriptions carefully as some have determinate growth and others indeterminate growth.

Determinate and semi-determinate varieties:

San Marzano – If you want to make authentic Neapolitan pizza, you’ve got to grow San Marzano tomatoes. This is the type that is used in traditional pizza sauce. This celebrated plum tomato also makes an outstanding sauce for pastas. The slender fruits grow around 3 inches long with blunt tips and have a rich, full flavor. Semi-determinate growth habit.

Roma VF – Roma tomatoes are one of the most popular plum tomato varieties grown in home gardens. The VF in the name signifies resistance to fusarium and verticillium wilt. The plants grow about 4 feet tall and are extremely productive, yielding the majority of their medium-sized fruits in a short window, convenient for sauce making or canning. Determinate growth habit.

Banana Legs – Banana Legs is a fun plum tomato to grow in big pots or garden beds. The plants are prolific and produce dozens of bright yellow, sausage-shaped fruits which grow up to 4 inches long. The flavor is slightly sweeter than San Marzano. Determinate growth habit.

Sunrise Sauce – A recently introduced hybrid paste tomato Sunrise Sauce produces a dozens of stocky plum-shaped fruits that are bright gold in color. The flavor is sweeter than other paste varieties and the fruits are produced over a short period of time. This makes it easier to cook large batches of sauce. The determinate growth habit makes this a good choice for containers or small spaces.

Indeterminate varieties:

Amish Paste – This Slow Food Ark of Taste listing is an heirloom variety with long cylindrical fruits that taper to a point. Amish Paste has a delicious rich flavor that makes a sublime sauce. We also love to slice them into salads and salsas. Indeterminate growth habit.

Big Mama – As you may expect from the name, Big Mama produces big tomatoes! The bright red fruits are up to 5 inches long and 3 inches across. Expect a flavorful harvest for tomato sauces, canning, and soups. Indeterminate growth habit.

Speckled Roman – The gorgeous red fruits of this open-pollinated plum tomato are streaked and striped in bright gold. They grow up to 5 inches long and each plant yields a heavy crop of the dense, tangy tomatoes. Indeterminate growth habit.

Pozzano – For the past three years, I’ve been growing Pozzano in my polytunnel and raised garden beds. It’s a hybrid variety with resistance to blossom end rot, fusarium wilt, tomato mosaic virus, and verticillium wilt. The thick-walled fruits have the classic paste tomato shape and blunt tips. Indeterminate growth habit.

For more information on growing tomatoes, we recommend the below articles as well as the awesome book, Epic Tomatoes by Craig LeHoullier:

Are you planting plum tomatoes in your garden?