5 Reasons Why Your Tomatoes Not Turning Red

Tomatoes might not belong in a fruit salad, but they sure do make a great addition to a vegetable garden. One of the best plants to propagate for food purposes, tomatoes tend to be easy to grow and delicious to add to a variety of kitchen dishes.

However, sometimes you can run into issues with your tomato plants—namely, tomatoes not turning red.

It can be frustrating to watch your tomato crop refuse to ripen, especially when you have salsas to make and pasta sauces to can. So, why are your tomatoes not turning red, and what can you do about it?

Let’s take a closer look at tomatoes, how they ripen, and what could be the reason behind tomatoes not turning red. And, most importantly, we will discuss some ways to solve the problem and ripen your green tomatoes indoors.

Interested? Then read on for more information!

When Do Tomatoes Turn Red?

When Do Tomatoes Turn Red

When can you typically expect your tomato crop to turn red and ripe? That’s a good question, and it’s an important one to consider before despairing over your still-green produce.

Tomatoes on the vine typically ripen between six and eight weeks after the blossoms have been pollinated. This time frame will depend on the variety of tomato, the temperature, and the growing season, but it generally holds true.

Thus, if you have planted your tomatoes and had mature flowers around the end of April to the beginning of May, you can expect tomatoes to ripen around mid-June or early July. However, this is still not an exact metric and will vary depending on weather and plant conditions.

Why Do Tomatoes Turn Red?

Keep in mind that not all tomatoes turn red when they are ripe—it depends on their type. Several heirloom varieties remain green when ready to eat, or even orange or light yellow. However, for the typical tomato that turns red when ripe, the science behind it is fascinating.

The two substances that combine to create the red hue of a ripe tomato are lycopene and carotene. These are only produced in temperatures between 50 to 80°F, which is why tomatoes are typically a warm-weather product.

The actual red color reaction is triggered by a chemical called ethylene, an odorless, tasteless substance that is produced by the tomato plant itself as the fruit matures. This ethylene interacts with the lycopene and carotene to turn the tomatoes red and ripen them.

However, these natural chemical productions and reactions can be easily slowed or halted altogether by a variety of factors, including weather, temperature, stress to the plant, and more. And this generally results in tomatoes not turning red or ripening properly.

5 Reasons Why Your Tomatoes Are Not Turning Red

Gardeners everywhere have struggled with tomatoes not turning red, and there can be several reasons for this issue. From weather to overstressing the vines, let’s look at the top causes of why your tomatoes won’t ripen.

Reasons Why Your Tomatoes Are Not Turning Red

1. Hot Weather

Though tomatoes can thrive in hothouse conditions, if the weather is just too warm, it virtually roasts the plant and will affect your tomato ripening times. Because of the heat, the compounds that produce typical red ripeness are not produced, and ripening is slowed significantly, or even stopped.

The best temperatures for tomatoes to grow and ripen are between 70 to 75°F. This keeps the fruit at an even temperature, and allows for the chemical reactions that create the ripening pigments to happen, turning the fruit from green to red or orange.

2. Cold Weather

Alternatively, the weather could be too cold for your tomatoes to fully ripen. This can be a major issue if you are in the middle of your growth period for tomatoes and either a cold snap occurs, or the end of the season comes sooner than expected.

Just like with high heat, tomatoes won’t ripen properly when conditions are too chilly. You can try to wait out the cold spell if it will be short, or bring the plants inside if it persists. However, you might not get that bright red ripeness if the plant has been damaged by frost.

3. Overloaded Vines

If you struggle with tomatoes not turning red, your vines might be overloaded with fruit, and the stress that it causes can affect the ripening of your entire harvest.

Because plants that are overloaded with fruit will be forced to ration their available energy between all of its produce, the entire ripening process will be slowed. It’s a good idea to keep your tomato plants harvested and healthy, so their limited energy is not overstrained by trying to grow too much produce at one time.

4. Wrong Tomato Variety

Growing season times change depending on where you live, and this affects the variety of tomatoes that you should plant. Some types of tomato take longer to ripen than others, and if your growing season is quite short, it can adversely affect your harvest and cause tomatoes to not turn red.

Make sure the tomato variety is correct for your location’s specific growing season. Keep in mind that it typically takes tomatoes between six to eight weeks to ripen after the blossoms are pollinated, with some hybrid varieties taking a shorter time to mature.

5. They’re Not Red Tomatoes

As a last option, maybe tomatoes not turning red in your garden is simply because they are not the type that does turn red. Many heirloom tomato varieties ripen into different hues, and your tomatoes could be one of these types.

For instance, if you are growing “garden peach” tomatoes, they turn a light color when ripe, and don’t even come close to turning crimson. It’s a good idea to double-check the type of tomato plant you have, and make sure you know what their ripeness looks like.

Tomatoes Not Turning Red? 10 Ways To Ripen Them On The Vine

Before you give up on a crop of tomatoes that is not turning red, don’t despair. There are many tricks you can employ to encourage your fruit to ripen on its own, before picking them while they’re still green. The following are some tried and tested ways to get tomatoes to ripen while still on the vine.

tomatoes Ripen On The Vine

1. Add Some Shade

If you notice tomatoes not turning red and temperature is rising, it’s time to add some shade to the equation. Because heat can prevent the lycopene and carotene production that causes tomatoes to ripen, putting up some form of shading should help your tomato plants cool down and continue the process.

2. Harvest Tomatoes Regularly

Prevent your tomato plants from being overloaded by picking fruit regularly. This might require you to remove some tomatoes that are not quite ready yet, in order to leave room for others to ripen completely, but you can always mature those green ones indoors.

3. Pick Tiny Tomatoes

If you notice a lot of very small tomatoes on the vines as the end of the season approaches, it’s best to pick them off. This will allow your tomato plants to focus their energy on ripening the larger, more mature tomatoes instead of splitting energy to share with the baby tomatoes that likely won’t ripen in time.

4. Top The Tomato Plant

Topping is the process of cutting off the primary stem of your plant. This prevents energy from being diverted to growing new stems or leaves, and instead channels it into ripening tomatoes on the remaining vines. Try topping if your plants are growing too vigorously.

5. Cover Tomato Plants At Night

To protect your tomatoes from cool nighttime temperatures that can affect ripening, try covering them overnight. Using a row cover will help regulate the temperature and keep them warm as night falls.

6. Prune The Plant

By removing some of the new leaf or vine growth, you can refocus the plant’s energy into ripening tomatoes that are already present. If your plant is incredibly leafy, trimming back some of the foliage will also help with airflow, creating healthier, hardier tomatoes.

7. Pinch Off The Suckers

Tomato plants only have so much energy generated by the nutrients of the soil and their photosynthesis abilities, so it’s best to channel as much of that as you can into ripening your tomato fruits. Identify any smaller stems sprouting from vines, called “suckers”, and pinch them off, removing their energy draw on the entire plant.

8. Remove Tomato Plant Flowers

Once the flowers on a tomato plant have been pollinated, successful blossoms will slowly turn into fruit over the course of two months or so. However, that also means new flowers on the plant are unlikely to turn into usable produce in the same season.

So instead of allowing new blossoms to divert energy away from growing the fruit, pick them off and dispose of them.

9. Slow The Watering

By slowing the water intake of your tomato plants, it gives a clear message that the season is ending, and that they should ripen the fruit. Instead of using the moisture to grow new vines or leaves, the plant should channel available resources to maturing the fruit already growing.

10. Cut Off Diseased Leaves

Diseased leaves on tomato plants can take a variety of forms, but the most common signs are yellowing or discolored leaves. Grab your pruners and trim these growths off the plant to force all energy back into the healthy vines and fruit. Plus, by removing diseased parts of your plants early, you can prevent the issue from spreading further.

How To Ripen Green Tomatoes Indoors

So, you just looked out into your garden and saw tomatoes not turning red. Now what? Don’t worry too much—there are several ways to salvage your tomato crop without having to start from the beginning!

Read on for five ways to ripen your green tomatoes safely inside the house.

tomatoes On The Vine

1. Hang Upside Down

If the season is ending and your tomato plants are still sporting green produce, you can dig out the entire plant and hang it upside down to encourage ripening. This might seem drastic, but keep in mind that most tomato plants do not regrow on their own after winter anyway.

Take all the tomato vines, bind them together with twine, and hang them upside down in a warm area. Many people like to hang them in a heated garage or warm greenhouse instead of the kitchen, as gravity can tug fruits off and make a splattery mess on the floor.

2. Pair With Other Fruit

Fruit like apples and bananas are great for helping others to ripen, so if you struggle with tomatoes not turning red, try pairing them in the same sealed container. This seal is important, as it will keep all the ethylene produced inside, as well as help moderate temperatures.

In fact, if you clump apples or bananas with tomatoes in a glass jar, you will not only enhance the hothouse conditions of the enclosure, but you will also gain a nice centerpiece!

3. Place In A Paper Bag

If you don’t have too many tomatoes not turning red, the paper bag method can be a great option.

Simply pop the green tomatoes into a paper bag, then fold the top to seal it, trapping in the ethylene that is produced. Keep an eye on it regularly and remove any moldy fruit, leaving ripened tomatoes behind in a few days.

4. Wrap In Newspaper And Box Them

If you have a larger harvest of unripe tomatoes, this method is a great option. Wrap each tomato in newspaper, with a small opening at the top for moisture to escape. Then, stack the wrapped tomatoes into a large cardboard box, up to two layers deep.

Close up the cardboard box and set it aside. Make sure that you check inside occasionally for moldy tomatoes to remove, and allow the produce to ripen.

5. Ripen On The Windowsill

Though this is one of the most common methods that people use for ripening green tomatoes, it actually is the least preferred. Using sunlight will help the fruit ripen, but too much time in direct rays will have negative ripening effects, just like when the entire plant itself is growing in very hot weather.

The best way to use the windowsill-sunlight method is by rotating them routinely so that one side does not get all the sun at a time. Try to move the crop around and allow them to evenly bask in the sunshine, and enjoy the process of watching—and smelling—your tomatoes ripen!


Final Thoughts

Tomatoes are one of the best plants to propagate for anyone who wants to eat fresh garden produce of their own. They are generally an easy plant to care for, and the flavor of fresh tomatoes is unmatched.

However, even the best gardeners can be faced with the issue of tomatoes not turning red. It can be frustrating, but ultimately is surmountable.

With some of the right methods to help your vines grow more effectively, and tips that help you to turn green tomatoes into ripe, red beauties inside the house, you can rest easy knowing that your garden tomato crop is in good hands—your own!


Do you want to learn even more about tomatoes not turning red? Let’s dig a little deeper and unearth the rest of the dirt on growing tomatoes and the ripening process.

How Do I Get My Tomatoes To Turn Red?

Are your tomatoes not turning red on the vine? You have a few options for fixing this issue, including taking steps to make the tomato plant healthier and more energetic, or simply harvesting the green tomatoes and ripening them inside the house.

Try pruning, shading, or underwatering your tomato plants to get the fruit to turn red. Or, if it’s too late in the season, use one of the in-house tricks for ripening green tomatoes, such as putting them in a paper bag or hanging the entire plant upside down.

What To Do With Tomatoes That Don’t Turn Red?

You can still eat green tomatoes! If you cannot get your tomatoes to turn red, even after taking them indoors and using all the ripening tricks, try making your green produce into a delicious green tomato salsa verde, or you can make fried green tomatoes for the entire family to try.

How Long Until Tomatoes Turn Red?

Tomatoes will take between six and eight weeks to fully ripen as they grow from a tomato blossom, but once the fruit is fully grown it should turn red anywhere from a week to twenty or more days. Of course, this will ultimately depend on the plant variety and growing season.

Do Green Tomatoes Turn Red After Picked?

You can successfully turn green tomatoes red after picking them, if you use the right methods as outlined previously. By harnessing the natural ethylene produced by green tomatoes, you can expedite the ripening process and get red tomatoes in the end.

How Long Does It Take A Cherry Tomato To Turn Red?

Cherry tomatoes take significantly less time to turn red than their larger counterparts, such as beefsteak tomatoes. Cherry tomatoes ripen about 65 to 70 days after planting, giving you a sizable and harvestable crop in a short time.
Additionally, keep in mind that not all varieties of cherry tomato turn red when ripe—yellow and orange cherry tomatoes are also very popular in gardens, and they only deepen in their colors when mature.

How Often Should Tomatoes Be Watered?

Tomato plants should be watered every two or three days over the summer. This will prevent them from drying out, but also avoid overwatering that can damage the root systems and virtually drown the plant within the soil. If your plants look limp, you can add more water, but do so cautiously.

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