Determinate vs Indeterminate Tomatoes: What they are and why it matters.Tomatoes
With the vast options of heirloom tomatoes, it’s hard to choose which ones to grow. And then you have to decide between determinate or indeterminate tomatoes. What does that even mean?
Understanding the difference between determinate tomatoes and indeterminate matters because it determines how you will care for your tomato plants and how you will harvest your delicious heirloom tomatoes.
Do you love tomato plants that spread and seem to produce forever? Or are you looking for a compact tomato plant that can grow in a small space?
Do you want a steady supply of tomatoes all summer long or a huge harvest all at once to make and preserve your favorite sauce?
If these questions matter to you, you’ll want to know the difference between determinate and indeterminate tomatoes.
Determinate vs. Indeterminate Tomatoes
Tomato varieties are either determinate or indeterminate. You can tell two things from knowing which type of tomato you have. First, you’ll know how it will grow. Second, you’ll know how it sets fruit so you can anticipate the harvest.
What are Determinate Tomatoes?
Determinate tomatoes have a fixed size. This means the plant will stop growing at the fixed point that is the typical size for that tomato variety. You may see determinate tomatoes referred to as “bush” varieties.
Once the tomato plant grows to its fixed size, it starts putting out flowers and fruits. Typically the mature size of a determinate tomato plant is 4 feet tall. Once it has put all its energy into producing tomatoes, the plant is done, and it will die.
When a determinate tomato plant starts producing flowers, you know that it has stopped putting energy into growing larger. Instead, it is now focusing its energy on making seeds, which means producing tomatoes.
Tips for Growing Determinate Tomatoes
Some things to keep in mind when growing determinate tomatoes:
- Determinate tomatoes benefit from some support to hold the branches once they are full of all those glorious tomatoes. Put up tomato cages when the plants are still small.
- Apply fertilizer when first transplanting and then when they start setting fruit.
- Plan on the tomatoes ripening within a 2-week window for harvesting.
- You don’t need to prune determinate tomatoes. However, you will want to remove leaves or fruit that touches the ground. This will help prevent soil-borne diseases.
- Determinate tomatoes can be grown in containers. Their compact growth makes them easier to maintain.
Determinate Heirloom Tomato Varieties
Marglobe tomatoes were first introduced in 1925. They have earned an enduring reputation as excellent canning tomatoes. They are disease-resistant and produce deep red globe-shaped tomatoes 7 to 10 ounces in size.
Roma tomatoes are frequently used in cooking and fresh salads. They are thick-walled and meaty. The bright red tomatoes average 3 inches long and have small seed cavities.
Homestead tomato is a semi-determinate variety that is very heat tolerant and reliably sets fruit in high temperatures. These crack-resistant tomatoes are mid-sized at 8 to 12 ounces. They have great flavor and are ideal for sandwiches, salads, and preserving.
Rio Grande tomatoes have a sweet flavor that is excellent for processing or just popping in your mouth. The above-average yields of plum-shaped tomatoes make this a perfect choice for home gardeners.
San Marzano tomatoes are a famous sauce tomato long cultivated in Italy. Small seed cavities with thick, dense, meaty flesh help this tomato cook quickly into a rich tomato sauce. These disease-resistant plants produce an abundance of 5 to 6-ounce fruits.
What are Indeterminate Tomatoes?
Indeterminate tomato plants have no size limit. They are often referred to as vining tomatoes. These plants will continue growing as long as the growing conditions are favorable. However, the cold weather will eventually kill them off.
Plan on your indeterminate tomato plants being at least 6 feet tall. Most will grow much taller with nutrient-rich soil and warm sunny days. These overachievers will produce flowers and fruit while still sending out more vines. So there’s really no end to your tomato harvest until the first fall freeze.
Indeterminate tomatoes are a good choice for vertical gardening. You can save space by having them grow up an arch.
Tips for Growing Indeterminate Tomatoes
Indeterminate tomato varieties will need more maintenance throughout the growing season.
- Indeterminate tomatoes will need big, sturdy supports. Plan ahead and put in a trellis or other support system that can handle the size of 6 feet and taller. If you don’t want to use a ladder to harvest tomatoes, you can have them vine over an arch. You can read more about tomato supports in our blog on trellis ideas for tomato plants.
- Pruning can help keep the plants from getting out of control. Pruning also allows for better air circulation and sunlight to ripen the fruit.
Indeterminate Heirloom Tomato Varieties
Beefsteak tomatoes are large and juicy. They can weigh in at a pound or more! Slice these up to make incredible BLTs, burgers, and sandwiches.
Cherokee Purple tomatoes have a complex flavor that is mostly sweet with hints of smoky and acidic notes. This indeterminate heirloom variety has relatively short vines and large tomatoes.
Kellogg’s Breakfast tomatoes have a firm, meaty flesh with thin orange skins. The 1 to 2-pound tomatoes are excellent for slicing and have a tangy sweetness balanced with just enough acid.
Ponderosa Pink tomatoes have a deep pink hue and grow up to 2 pounds. This beefsteak tomato has low acidity and very few seeds. Its complex flavor is good for slicing or cooking.
Indeterminate or Determinate? Which tomato should I grow?
There are a few factors that will help you decide which type of tomato to grow.
How long is your growing season? Indeterminate may take longer to begin setting fruit. But if you have a long growing season, they will continue producing until it gets too cold.
Do you want to grow tomatoes in containers? Determinate tomatoes are a good choice for container gardening.
How do you want to use your tomatoes? If you want to preserve a big batch of your favorite sauce, try a determinate variety. Roma and Marglobe are well-known heirloom varieties used for making sauce and canning.
Do you want big tomatoes to eat fresh all summer long? Try the many indeterminate heirloom varieties popular for fresh eating, such as Mortgage Lifter and Beefsteak.
Which tomatoes are better? Determinate or indeterminate?
It’s not really a matter of one type being better than the other, indeterminate or determinate. Instead, it’s all about knowing the differences and deciding what makes the most sense for you. And sometimes, it ends up being a choice based on a specific color or flavor profile you want.
It makes gardening easier when you know what to expect and what’s normal for your plants. So now that you know the difference between indeterminate and determinate tomato plants, you won’t be surprised by 10 feet tall indeterminate tomato plants! And when your Roma tomatoes stop growing, you’ll know it’s time to make plans for canning a batch of your favorite sauce.
With all these determinate and indeterminate varieties, you'll have plenty of options for which tomatoes to grow.