Determinate and Indeterminate Tomatoes

This article has everything you need to know to understand determinate and indeterminate tomatoes, so that you can choose the right variety for your vegetable garden!

Are you thumbing through seed catalogues and wondering which tomato varieties you should try this spring?

When planning your garden and planting and harvesting your tomatoes, it is really important to understand whether you have a determinate or an indeterminate variety. This key trait makes a huge difference to how well your tomato will grow in your specific conditions.

It also helps you be successful if you know the specific needs of the plant, because the two types have have different growing requirements. And of course it matters what you want to use the tomatoes for.

Maybe you want to try a few plants of each if you have room.

So let’s start by describing determinate tomatoes.

Determinate Tomatoes

Determinate tomatoes have a set lifetime. They will grow to about 4 feet tall and no more. They produce all (or most) of their tomatoes at once, and then begin to decline. While you may get several more tomatoes after that first harvest, they will generally not be as big or as many.

They are often called “bush” tomatoes due to the fact that they only grow to a set size.

Why does the plant know to stop growing? Actually, the branches of the tomato plant end in flowers. So the plant will flower and set fruit, but there are no additional branches to set new flowers. Whereas indeterminate tomato branches will end in leaves and continue to branch out and produce new flowers.

Commercial farmers tend to favor determinate tomatoes because they can get higher yields all at once, and then will rip out the plant and replant.

Some more things you need to know about determinate tomatoes:

Determinate tomatoes are good for small spaces and patio gardening
Determinate tomatoes need less staking, because they are not as tall
Determinate tomatoes are excellent for short growing seasons
Determinate tomatoes are great choices for succession gardening
Determinate tomatoes do better in containers because their lifespan is shorter and nutritional needs less demanding
Determinate tomatoes are perfect for canning when you need a big harvest all at once
Determinate tomatoes tend to be smaller, faster ripening varieties. Generally they are not beefsteak styles.

Examples of determinates:

Roma
San Marzano
Celebrity
Ace 55
Amelia

Indeterminate Tomatoes

Indeterminate tomatoes do not have a set lifetime or height. They will keep on growing taller and bigger until they are killed by frost. Unlike determinate tomatoes, they will produce tomatoes over a longer period of time and continue to grow and flower and fruit throughout the season.

Because they keep growing, they are often referred to as vining tomatoes rather than bush tomatoes.

As discussed previously, determinate tomato branches end in flowers, stopping the ability to grow. Conversely, indeterminate tomato branches end in leaves and continue to branch out. They grow axial branches (or suckers) between the main stem and the branch, which will then continue to fruit and branch out over and over again until they are stopped by frost.

Indeterminate tomatoes tend to be bigger and juicier tomatoes, too.

Some more things you need to know about indeterminate tomatoes

The plants grow much taller – depending upon the length of your growing season , they can be 8 or 10 feet tall
The plants need a lot of room and do better with good spacing and airflow in between plants
Indeterminate tomatoes require super strong supports; 6 foot supports is an absolute minimum.
Indeterminates can be harvested all season long
Indeterminate tomatoes are heavy feeders and need regular fertilization
Indeterminate tomatoes do not do as well in containers
Indeterminate tomatoes include the heaviest beefsteak style tomatoes
Most cherry tomatoes are indeterminate
Many heirloom varieties are indeterminate