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Why Did The Tomato Turn Red – Reason Behind Tomato’s Red Color

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The tomato is a fruit grown for its beauty and flavor. They come in all colors, including green when they’re just born from seedlings to red as they mature on the vine. If you’re one of those people who has a tomato plant, you must be thinking, “why did the tomato turn red.”

Although it is a riddle with so many amusing answers, there is a scientific answer to this question that we will answer in this article. So, take a deep dive with us to know the science behind tomatoes changing from green to red.

Why Did The Tomato Turn Red
Still life with tomatoes via Flickr

Why Did The Tomato Turn Red

Tomatoes are always a great addition to any meal, and you can’t beat their delicious taste. Depending on the variety, you might have known that tomatoes change colors as they mature from green into reds or oranges. But did you also know there’s another color change happening deep inside?

Over time certain chemicals start breaking down chlorophyll in tomatoes while creating new ones like carotenoids which give off different pigments giving a red hue. As a result, the tomato changes color from green to yellow and ultimately turns red as it ripens.

This gradual change in appearance is due to a breakdown of chlorophyll, which produces lycopene responsible for tomatoes’ red color.

Two Pigments In Tomatoes

Tomatoes can change the color of their skin due to two pigments, chlorophyll, and lycopene. Although tomatoes contain various carotenoids (colored compounds), i.e., beta-carotene and xanthophylls, the chlorophyll and red lycopene are dominant.

1.     Chlorophyll

Chlorophyll is the most common pigment in unripe fruit and many vegetables. It is found in virtually all photosynthetic organisms, including green plants and cyanobacteria. Unripe tomatoes are green due to chlorophyll.

2.     Lycopene

Lycopene is the compound that gives tomatoes their signature red color. You can also find it in other fruits and vegetables, such as carrots or watermelons. When the tomato is ripe, the chlorophyll is degraded, and the red lycopene color dominates. This compound has several health benefits, including:

  • Powerful antioxidant
  • Gives sun protection
  • Improves heart health
  • Lower risks of cancer
Cherry tomatoes red and green Why Did The Tomato Turn Red
Cherry tomatoes red and green via Wikimedia

Process Of Tomatoes Turning Red

With the arrival of harvest time, the temperatures fall (in the autumn months), and chlorophyll starts breaking down. Lycopene takes over as a result of this process- it’s what gives tomatoes their red coloration.

You can watch the process of turning your tomato from green to red once all the lycopene pigments have leached out. Tomatoes must be at an advanced stage for this transformation, or else they will remain unripe and therefore tasteless as well.

Once that has happened, it’s time for ethylene – an odorless gas that causes fruits like tomatoes to become more flavorful over time due to its ripening power. As a result, their sugar levels rise simultaneously, and they become more tender and sweeter.

Tomatoes are a fruit that grows quickly. They can reproduce and mature within months, but it takes just days for them to become red through their ripening process. That’s the reason farmers harvest tomatoes even if they are green and then apply enough ethylene before being shipped off for sale.

Factors Affecting Tomato’s Red Color

Tomatoes are a delicious and nutrient-rich ingredient in our diets. They are a great source of vitamin C and can be eaten, raw, or cooked. Here are the factors that are linked to the tomato’s red color.

Tomato Variety

The variety determines the way a tomato turns red. The smaller tomato varieties are faster at turning shades of red compared to larger ones. The large fruit varieties take longer on average to ripe fully. For example, cherry tomato takes less time to ripen while beefsteak tomato ripening takes time as it is a larger variety.

Depending on the variety, a tomato takes a long time to reach the mature green stage. Therefore, the red color cannot be achieved, even if forced by modern technology, because tomatoes have not yet reached maturity. Only when fully ripe will these fruits produce their signature red hue.


The process of a tomato turning from green to red can take up some time, and it all depends on the temperature.

To produce lycopene or carotene that helps make this happen, temperatures between 50-85 degrees Fahrenheit are needed. Any temperatures below or above this scale will make tomatoes remain green for a long time.

Tricks To Initiate Tomato Ripening Or Their Red Color

When tomatoes are not ripening, they must not have the right conditions to mature. A few things preventing this fruit from maturing: some varieties grow faster than others, varying temperatures also affect how fast each type will ripen.

Here are the tricks which might help you trigger your tomato maturing process.

Prune Them

Tomatoes are one of the best vegetables for summertime. Properly pruning them throughout the season will result in more red tomatoes.

Cut Off New Growth

Topping the plant will give it a burst of energy, and cutting off all new growth will help tomatoes ripen faster.

Pick Off Flowers

Since it takes a couple of months for tomatoes to ripen after the flowers on their vine, have been pollinated. So, pick all of these flowers away as they are of no use.

Pinch off Suckers

Suckers are the smaller stems that grow between branches and leaf joints and steal energy from neighboring leaves. So be sure to remove them as soon as possible because these things don’t produce any fruit or vegetables after all.

Remove Tiny Tomatoes

Pluck tiny tomatoes off your vine as they are stubborn to become red.

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The tomato is a fruit that changes color as it ripens. The green tomatoes start with chlorophyll, which slowly breaks down, and red pigment lycopene is synthesized.

  • The green color of tomatoes is due to a green pigment, “chlorophyll.”
  • The red lycopene compound gives tomatoes their richly pigmented appearance.
  • When a tomato is mature, it turns red because of the breakdown in its chlorophyll.

If there are any questions or concerns, please let us know in the comments.