Tomatoes not turning red is a problem arising from different factors like bad variety choice, incorrect watering, poor lighting conditions, heat stress, and cold temperatures. If you do something quickly, all your efforts to grow these plants will be well-spent.

Tomatoes Not Turning Red

Luckily, it is easy to deal with this problem, which we discuss in this article. So, continue reading.

What Are the Causes Behind Tomatoes Not Turning Red?

The cause behind tomatoes not turning red quickly can be that you are growing a late-maturing variety, however, there are others. If the variety is early-maturing, improper watering and lighting conditions can cause it. In addition, temperature stresses can also play a big part in fruit discoloration.

– Late Maturing

If the tomatoes are not becoming red, check whether you are growing a late-maturing variety or not. Different varieties have different ripening times, but late-maturing ones take more time to develop fruit colors.

Generally, tomato fruits ripen within 40 to 70 days after transplanting. People also ask what month do tomatoes ripen? It is usually in late June and early July, but the exact time can vary.

– Improper Watering

The plant faces some issues if the variety matures early and tomatoes still need to turn red. In most cases, the over-application of water causes problems with color change. The reason is that when you add lots of water after the fruit formation, plants spend it developing new fruits and leaves instead of focusing on the maturation of already set fruits.

So, plants will prioritize new vegetative and floral growth over fruit ripening if you apply water even after setting off fruits. However, under-watering your tomato will also have a negative effect on your tomatoes.

– Incorrect Lighting

Improper lighting conditions can also cause plants to have green tomatoes instead of red ones. It is because the light is critical for plants to generate energy.

In addition, they use it to photosynthesize, which helps them stay healthy. Therefore, you should grow tomatoes in those spots where they can easily get eight hours of light.

Causes of Tomatoes Not Turning Red

Decide on the site carefully because the physiological process will take a hit if you choose the wrong spot. As a result, fruit maturation can get delayed. Such plants can still ripen their fruits. However, the fruit will be small, and the quality will be poor. So, plant tomatoes in a well-lighted area only.

– Too Hot or Cold Temperatures

Tomato plants prefer 50 to 85 degrees Fahrenheit for growth. However, for the smooth ripening of fruits, the ideal temperature is 70 to 85 degrees Fahrenheit. Plants will find it hard to mature fruits easily if it is higher or lower than this.

The reason 70 to 85 degrees Fahrenheit temperature is ideal is because the synthesis of carotene and lycopene is more in it. These two carotenoids give red colors to tomatoes and many other fruits like red ball peppers, watermelons, etc.

Tomatoes love warm temperatures so that they can withstand heat stress. Still, a constant temperature of more than 90 degrees Fahrenheit can cause moisture within the plants to evaporate, causing water deficiency.

But the main problem regarding fruit color will be the inhibition of carotene and lycopene. So, fruits in excessive heat appear discolored and sick.

Similarly, growing tomatoes can be frustrating if you live in a colder region. However, tomatoes hate cold stress more than heat stress. It is because most of the physiological functions and synthesis of carotenoids get limited when the temperature drops below 50 degrees Fahrenheit.

So, when it’s cold outside, your “tomatoes not ripening, turning brown” nightmare will come true. Therefore, check the current temperature to confirm whether plants face heat or cold stress.

– Lack of Nutrients

When you see cherry tomatoes not turning red, they might face nutrient deficiency. The availability of nutrients does not matter when it comes to the ripening of tomato fruit. However, it is crucial to give the redness.

Generally, the deficiency of calcium, potassium, and magnesium does not let the fruits have their natural colors. Due to nutrient stress, the tomatoes might stay fully green or half red. So, how can you help tomatoes turn themselves red? It’s time to find out.

How Do You Turn Tomatoes Red?

To turn tomatoes red your quickest fix is to stop watering to ripen green tomatoes. This will force plants to mature their fruits and focus on coloration. Furthermore, you can cut off any new plant growth to make them spend their energy on fruits only.

– Wait for Maturing Time

When tomatoes do not turn red, check the maturing time of the variety you have sown. If time is left, wait a few more days to see if it gets red. So, how long does it take for tomatoes to turn red? Usually, these things are mentioned on the seed packet.

– Add Water Smartly

You should water tomato plants after every three days to prevent any problems. But when they develop green tomatoes that refuse to become red, you should stop watering and let the soil get dry.

When you don’t water plants, they will stop focusing on vegetative growth and flower production. Instead, all the energy left will be directed to the maturation of the fruits, and you will see them turning their color to red within a week.

– Grow and Store Indoors

We suggest you do indoor gardening rather than outdoors to avoid any color problems. It is because it is easier to manage the temperature, light, and watering when you grow them inside. Still, if you have already grown them outside, there is no need to worry. You can store green tomatoes indoors.

People often wonder, “do green tomatoes turn red after picked?” And yes, they do. But, you will have to handle them cleverly, or the redness will never appear. So, how to turn green tomatoes red indoors?

We suggest you harvest all the green and ripe tomatoes and put them in a closed environment (preferably a greenhouse). The ripe ones will produce ethylene gas which will induce the ripening in the unripe and greener ones. As a result, all of them will become red shortly.

Stay calm when you still face the problem of tomatoes not ripening in the greenhouse. As mentioned above, it is really easy to manage the discoloration problem when you have fruits indoors.

We suggest you place ripening tomatoes in a paper bag with bananas and apples. These two fruits also release ethylene gas, which helps tomatoes get mature and develop redness quickly. Make sure to seal the paper bag tight for a few days if you want faster results.

– Mulch the Soil

It is super important that plants stay free from any temperature stress if you want the fruits to ripen and develop true colors. Some suggest you bring the pots inside when the outside is too hot or cold for plants.

Remedies for Tomatoes Not Turning Red

We suggest mulching to deal with temperature complications and enhance tomato ripening. It is really simple to do, as you will have to follow these three easy steps:

  1. First, clean the soil of any dirt and add a little water.
  2. Cover the wet soil with mulch. You can use grass clippings, straws, compost, rubber pellets, or a mixture. Cover the whole soil completely with this mulch.
  3. Add water again to settle down the layer.

This mulching layer will act as insulation from both heat and cold extremes. This will let the soil temperature stay optimal, allowing all the internal processes to continue. As a result, plants will also feel the warmth. In addition, when this mulching decomposes with time, nutrients will release, making the soil even stronger.

But make sure not to add lots of water during the whole process. The moisture can get trapped inside the mulch, leading to fungal diseases like root rot. Also, don’t add a thick layer of mulch, or the roots will face oxygen stress.

– Don’t Allow Any New Growth

If you want the immature tomatoes to mature quickly, we suggest you cut off any new growth of suckers, leaves, etc. When you do this, plants spend their energy on fruit maturation and coloration instead of growing these new parts.

– Pluck Out the Late Flowers

If there are many green fruits on your plants, you should not allow any more flower production. This is because these late flowers usually do not set fruit as the temperature increases when the set arrives.

Even if fruit setting becomes successful, the quality will need improvement. So, plucking any late flowers you see would be best. This will allow plants to spend energy on proper tomato coloration instead of developing new flowers and fruits.

– Prune Leaves and Stems

If you want tomatoes to ripen faster, we also recommend you do the pruning of leaves and stems or suckers. You should remove the lower and older leaves you see using your hands only. Similarly, you can pinch off the suckers between the leaf joints and prune off such branches that do not have any fruits.

When you cut off these parts, the plants will direct their effort and energy into fruit maturation and coloration. That is why almost every tomato grower does pruning when the fruit set starts to occur.

– Follow Care Tips

For tomatoes to develop redness, you should also follow proper care tips. We suggest you harvest poor-quality fruits early because they have no value and keep others from attaining their colors.

Furthermore, choosing better varieties that ripen tomatoes quickly beforehand would be best. In addition, always keep your vegetable garden free from weeds. Weeds use most nutrients and water you add for main plants. This causes stress, and fruit coloration can get affected. So, follow these measures, and tomatoes will become red shortly.

Conclusion of Tomatoes Not Turning Red


In conclusion, red fruits on a tomato plant are necessary, or the whole effort seems wasted. However, they usually stay green because of different factors, and we discussed how you could fix all of them. Here are the key takeaways so that you don’t miss any important details:

  • Stop watering the plants to force them to change their fruit color from green to red.
  • Pinch out new suckers and prune off branches with no fruit to speed up tomato fruit maturation.
  • Do not allow late flowers to bloom, or the tomato fruit colors will not develop properly.
  • Do mulching to protect your tomato plant from temperature stresses (and ultimately fruiting complications).

That’s all about how to turn every tomato red.

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