All About Indeterminate Tomatoes

Tomatoes are a great addition to any size garden. They are easy to grow and maintain, which makes them an ideal crop for beginners. Plus, some tomato varieties produce bountiful harvests year after year. Do you live in an area with a long growing season or have the ability to bring your plants indoors over the winter? If so, you should consider planting indeterminate tomatoes this year.

What are indeterminate tomato plants anyway, and how do they differ from determinate varieties? Let’s find out!

What Are Indeterminate Tomatoes?

What does it mean when a plant is indeterminate? This term describes the growth habit of certain organisms. When something is indeterminate, it lacks a defined upper growth limit. 

Vining tomatoes such as the Santorini tomato generally exhibit indeterminate growth habits. These varieties of tomatoes continue to grow and bear fruit all season long. Other tomato varieties that exhibit bushy growth are typically determinate plants.

Determinate vs. Indeterminate Tomatoes

Is there a significant difference between determinate and indeterminate tomatoes? Which tomato variety should you grow in your garden? If you live in an area with a moderate growing season, you will likely see a similar yield from either plant type when the year is all said and done. Still, there are key differences in the timing of harvests that you should consider.

Indeterminate tomato plants start producing fruit earlier in the growing season. They continue steady production until growth is halted by external factors, such as frost. If you can bring your plants indoors for the winter, indeterminate tomatoes can continue growing for multiple years.

Indeterminate varieties allow you to harvest a continuous supply of tomatoes a few at a time. These productive plants are an excellent choice if you consume tomatoes regularly.

On the other hand, determinate varieties produce gallons of fruit late in the season. You will usually only get one or two of these bountiful harvests before determinate tomato plants start to die off.

The vast quantity of fruit you can collect in a short time makes determinate tomato varieties an ideal choice for canning. For the same reason, determinate tomatoes might lead to food waste if you don’t intend to eat the entire harvest or preserve the excess.

There are also a few semi-determinate tomato varieties that provide the best of both worlds. Such tomato plants produce multiple hearty harvests, but their growth is more constrained than that of indeterminate tomatoes.

How to Prune Indeterminate Tomatoes

After you plant your tomato seeds and nourish them from seedlings to budding vines, they will need special care. An essential part of growing hardy tomatoes is proper pruning.

It is essential to prune indeterminate tomatoes, as an unkempt tomato plant can quickly get out of hand and grow many feet in height. Furthermore, when growth is left unchecked, indeterminate tomato varieties put most of their energy into foliage growth instead of fruit production. This could leave you with a smaller crop yield.

You should be careful if you are new to pruning tomato plants. First, ensure that you are growing indeterminate tomatoes. Determinate tomato plants should not be pruned, as their overall growth is genetically limited. 

Once you are sure you have one of the many indeterminate varieties, you are ready to start pruning. Take it slow and follow these simple instructions diligently until you get the hang of it. Don’t worry if you mess up at first—most tomato varieties are reasonably resilient.

Step 1: Locate the Main Stem

This first step might sound unnecessary if you’ve never seen a tangled tomato vine. How hard can it be to find the stem? It can actually be somewhat challenging to sort it out from the many branches! The best way to single out the stem is to follow it with your finger from the ground to the tip of the plant.

Step 2: Find Fruit and Flower Clusters

Look carefully for branches bearing clusters of blossoms or tiny fruits among the many leaves. You want to avoid trimming any of these branches or the leaves. Instead, nestled between the main stem and the leaves are small shoots that don’t contain any flower clusters or fruits. These are called tomato suckers, which are essentially smaller tomato plants emerging from the main plant.

Step 3: Keep the Biggest Sucker

To find the biggest sucker, check near the lowest cluster of flowers. It will usually be sprouting up just beneath this cluster. You want to leave this big sucker alone so it can continue growing.

Step 4: Clip All Other Suckers

Now preen through the entire plant and clip every sucker besides the one you singled out in the previous step. Don’t be scared—this won’t hurt the tomato plant. Removing these shoots simply allows the plant to concentrate energy on fruit production. The cuts need to be clean, so use a well-sharpened garden knife or pair of pruning shears.

Step 5: Clean Up

Once you finish the initial pruning, you need to clean up the damaged stems and leaves. Remove any low-hanging leaves that could pick up pathogens from the soil. If your indeterminate tomato plant experienced extensive growth, you might need to do some heavy pruning and cleaning to ensure healthy growth through harvest.

Indeterminate Tomato Support Systems

Indeterminate tomatoes can grow up to ten feet tall. Without proper support, the stem could break once those delicious tomatoes start weighing the plant down. You need a support structure to ensure your tomato plant can produce fruit without any issues.

Determinate plants usually don’t need extra support since their compact size and bushy shape make them rather sturdy. However, if you are growing indeterminate vine tomatoes, you should invest in a trellis or tomato cage.

Once your tomato plant is about a foot tall, you can build a cage around it. To construct a tomato support cage, you can use trellis netting and stakes.

First, drive a few stakes into the soil more than six inches from the stem and ensure they are set and sturdy. Next, wrap the trellis netting around the stakes and secure them with twine. You might need to first guide the tomato suckers toward the cage walls. Once they start growing up the trellis netting on their own, they should be set for the season.

Indeterminate tomatoes are suitable for container gardening as well. Simply erect the cage around the container to provide the necessary support. Learn more about how to grow tomatoes in pots in our comprehensive guide.

Some gardeners like to grow indeterminate tomato varieties upside down. This allows the tomato vines to extend fully without dragging the ground. If you do this, just ensure the container is secured on sturdy hooks. Tomato plants can get very heavy come harvest time.

Should You Grow Indeterminate Tomatoes in Your Garden?

For tomato lovers, there are few things sweeter than plucking plump fruit from your own tomato plant. If you like having a steady supply of tomatoes all season long, then you might enjoy growing indeterminate tomatoes.

Excited for more tomato content? Then visit our tomato page for growing tips, comprehensive guides, and tasty recipes!