Last Updated on May 16, 2023
Are your tomatoes not turning red despite being big enough to be ripe and have been in the ground for long enough? This is a common frustration that many tomato gardeners face. Do not despair, there are ways to diagnose this problem and solutions to it. In this article, we will give you 14 tips for ripening tomatoes.
Tomatoes are some of the most common and versatile vegetables that are used in every household. Fresh garden tomatoes are some of the best and freshest you can ever taste. So it can be discouraging when your tomatoes don’t ripen when you expect them to. Keep reading this article to learn all about tomatoes not turning red.
Tomatoes are described as edible berries of the plant Solanum lycopersicum, which is commonly referred to as the tomato. The tomato plant originates from South America, Mexico, and Central America.
Many different types and varieties of tomatoes are used for different purposes, such as cooking, salads, pickling, etc.
Indeterminate tomato plant varieties are perennials in their natural habitat, however, they can be cultivated as annuals. Depending on the cultivar, plants can grow up to 1/2-4 inches in width.
Tomatoes can come in different colors too, with most of them turning red when ripe. As a result, it can be quite frustrating when tomatoes don’t turn red when you expect them to.
Why Are My Tomatoes Not Turning Red?
There are different reasons why tomatoes are not turning red.
The first and most obvious reason is that they may not be ripe yet. Tomatoes have a long growing season. Depending on the variety, they may take anywhere between 60 to more than 100 days from the day they are transplanted to when they are ready for harvest. If you are not sure what the exact timeframe for the ripening of your plants is, check the packaging, as this information is usually provided.
Another reason is that some tomatoes are just not red when ripe, so they can not be expected to turn red even when they are ready for harvesting. Some tomatoes have unique colors. Examples of these include;
- Sungold cherry, garden peach, and Persimmon, which are yellow when ripe
- Black krim, which is a beautiful black color
- Green zebra, which is a modern heirloom tomato that is known for its lime green color.
While these tomatoes have unusual colors, they are great to grow if you want to try something different.
As tomatoes mature in the summer, they can become big and overgrown. When it happens, the plants direct most of their energy toward producing more leaves and flowers, instead of ripening the tomatoes.
The number one cause of tomatoes not turning red when the time is right is temperature. Regular tomatoes will not turn red if the temperatures for their ripening are off. Temperatures above 85 degrees Fahrenheit are too high, and anything below 50 degrees Fahrenheit is too low. The bigger risk of the two, however, is the high temperatures that can often occur during a heatwave.
Outside the temperature range of 50-85 degrees Fahrenheit, the tomato plant is unable to produce enough carotene and lycopene that cause the color change for the ripening process. The best temperature for tomato ripening is 70-85 degrees Fahrenheit.
Although tomatoes love heat, too much of it can be bad. Extended periods of heat stress can cause plants to stop developing and this may prevent the tomatoes not to turn red. Too much cold temperatures stop the production of the carotene that is needed for the ripening of the tomato. This usually happens at the end of the growing season.
Excessive watering and feeding of the plants can also be bad. If tomato plants are provided with more nutrients than they need, it can cause them to direct their energy towards producing new growth instead of ripening the fruit.
When Do Tomatoes Turn Red?
Tomatoes have a long growing season. To be a tomato gardener, you must have a lot of patience. Tomatoes will turn red when ripe, provided all their growing and ripening conditions are being met. If you are unsure when exactly this time should be for the particular variety of tomatoes in your garden, check the packaging that the seeds or seedlings came in. The growth period of the tomatoes should be given there. If you do not have access to the packaging, a quick Google search might be helpful to estimate the approximate time you should expect your tomatoes to ripen.
Generally, most tomatoes take between 60 to just over 100 days to ripen. This is between the day they are transplanted into the soil and the day they are ready to harvest. The speed with which they ripen will depend on variety, environmental conditions, and the size of the tomato fruit. For example, cherry tomatoes ripen faster than larger tomatoes.
To get them to ripen at the right time, you have to plant them in the soil at the right time. The best time to do so is to start the seeds about 6-8 weeks before the last frost date.
Keep in mind that not all tomatoes will turn red. Some tomatoes are yellow, orange, purple, or even green when ripe. Know what the variety of the tomatoes you are planting is, so that you know what they should look like when they are ripe.
What to Do When Your Tomatoes Are Not Ripening
Both larger and small tomatoes such as cherry tomatoes not turning red can be due to various reasons, as we have already discussed. Here are 14 tips for ripening tomatoes when they won’t ripen.
1. Stop the plant from growing
One of the major reasons this happens is the result of overgrown plants. This then causes the plant to divert more energy into producing new plant growth, instead of toward the fruit and seed. One way to deal with this is to stop the plant from inefficiently utilizing energy. Do this by pinching or cutting off the top point of the plant that is growing, so that the plant will not get any bigger.
Also, cut off any new flowers that have not produced any fruit yet. They will never be able to do so as there is not enough time left in the growing season.
2. Cut off the outside shoots
Tomatoes are very strong growing plants and produce a lot of foliage. Even if you keep trimming them, shoots keep reappearing. You should always pinch off or cut off any side shots that develop after the plant has matured. Always keep an eye out for them and remove them as soon as they appear. This will save the plant from using energy for growth, which it should rather direct towards fruit ripening.
3. Trim back plant foliage
Like all other plants, tomatoes need light for good growth and health. If there is too much foliage that covers the plant and minimizes the amount of light that it gets, the plant will not grow very strong. Trim off as much of the foliage as you can without damaging the plant. This will enable the plant to get direct sunlight that will warm it up, helping to speed up ripening.
4. Provide heat
If you can provide your plants with some form of heat, it will help ripen them. If you can install grow lights that can increase the temperatures even slightly, the ripening process would speed up.
5. Move plants to an indoor area
Tomato plants are great for growing indoors. If your tomatoes were planted in a movable grow bed or pot, moving them indoors where you can control the temperature to make them more suitable for ripening will greatly benefit the plant.
6. Cut back on fertilizing
Excessive fertilizing of tomato plants can do more harm than good. Ideally, tomatoes should only be fertilized about 2-3 times during their entire growth cycle. Do not fertilize the plants when they are close to harvest, and this will cause them to direct energy towards growth and not ripening.
7. Reduce watering
Excessive watering can also delay tomato fruit ripening. Reduce the rate of plant watering by only watering when you notice signs of wilting on the plant. This can help to push the plant towards fruit ripening.
8. Wait for cooler temperatures
If your tomatoes are not turning red because of high temperatures, you may just have to wait until the weather cools and ripening resumes.
9. Hang the plant upside down
Uproot whole plants when tomatoes won’t ripen. Hang the plant upside down in a warm and dry room where it will be protected from extreme temperatures and frost. The fruit can ripen as the plant dies. When trying out this method, try to get some of the soil out with the root.
10. Put the tomatoes in a bag with a banana
If you still can’t get your tomatoes to ripen, try this trick of putting them in a bag with a ripe banana. The ripe banana releases ethylene which is a great promoter of tomato fruit ripening. If you choose to try this method, check your tomatoes regularly for any sign of rot. If you notice that any are starting to rot, remove them before they damage the others in the bag.
11. Put the tomatoes in a bag with a ripe apple
This method is the same way as the previous method described, just with a different fruit.
12. Pick individual tomatoes to ripen
You can also pick tomatoes individually to ripen them by placing them on window sills, and they will eventually turn red.
13. Plant the next crop of tomatoes on time
As more of a proactive way to ensure that your tomatoes ripen, plant them at the right time so that they have enough time in the growing season to grow and ripen before the temperature gets bad.
14. Pick the green tomatoes
If all efforts of ripening your tomatoes fail, you can pick them green. Green tomatoes are great for pickling.
Can Tomatoes Ripen Off the Plant?
Normally and ideally, plants should be left on the plant until they ripen, and then they can be picked off, However, some conditions occur that may require you to pick them off the vine and attempt to ripen them indoors. These factors are usually associated with environmental conditions such as temperature and frost.
You can pick unripe tomatoes and ripen them off the plant, provided that you can give them good ripening conditions as described above.
Why Are My Tomatoes Not Ripening? – Summary
Tomatoes are very easy plants to grow, as long as you know the variety and their ideal growing conditions. Key points to remember are that tomatoes won’t turn red if it’s too hot (above 85°F) or too cold (below 50°F), If your tomatoes do not grow well, they may be stressed and this may affect ripening. Smaller tomatoes are the result of stressed tomato plants.
Tomatoes produce carotene and lycopene which will promote ripening at the end of the growing season. Make sure that your plants are provided with good growing conditions so that they can produce enough carotene and lycopene.
Tomatoes are slow to ripen on the vine because they are overfed, overwatered, overgrown, or the weather is too cold. Adjust your maintenance schedules to get the best out of your plants.
We hope this article provided you with enough information, tips, and tricks that you will use to ripen your tomatoes that may not be turning red on their own.
An aquaculture specialist and freelance writer. Passionate about anything sustainable living, such as growing your own food, and if you can do it in conjunction with fish farming, even better! I currently work as an aquaculture researcher where I can expand and share my knowledge and skills on aquaculture, crop farming and adding value to wastewater by using it to grow food products. I enjoy reading and learning as much as possible, and writing is another avenue for me to share the knowledge I gain with others. I want my writing to inspire people to try their hand at gardening, whether indoors or outdoors. You can even start by keeping a few houseplants indoors to help you gain a bit of confidence if you need to.