Overwatering is one of the most common mistakes people make when they grow tomatoes and oftentimes it ends up killing the plants. It doesn’t have to be that way, though, if you know which signs to look for and how to save your tomatoes if they become overwatered.
I have definitely made the mistake of overwatering my tomatoes in the past, but now that I know what to look out for and how to save them if needed, I don’t lose my tomatoes to overwatering anymore. And you don’t have to either, which is why I have written this article.
In this article, I explain 9 signs you should keep an eye out for since they might indicate that you are overwatering your tomatoes.
After that, I explain some easy things I do to save my tomatoes when I give them too much water, which you can easily do to save yours too.
Lastly, I share some easy tricks you can keep in mind to avoid overwatering your tomatoes in the future.
How to Tell if Your Tomato Plants Are Overwatered (9 Signs)
Overwatering can kill your tomatoes and the best thing you can do to prevent that from happening is to learn which signs to look out for, so you can save your plants before they die.
That’s why I’ve made this list with 9 signs tomato plants tend to show when they are overwatered. After this list, I explain what you can do to save your tomato plants and how to avoid overwatering them in the future.
The plants won’t show all the signs until they have been overwatered for a while. Instead, the signs tend to come little by little, so it is a very good idea to learn about them, so you can react before it is too late. Let’s get into it!
1. The plants don’t perk up when you water them
Tomato plants tend to perk up a bit after you water them. Especially on warm, sunny days since the plants use (and therefore need) more water than on other days, which can make them look a bit droopy until you water them.
Overwatered tomato plants don’t perk up when you water them but instead stay droopy-looking. This is because their roots already have all the water they need (and more) and might be starting to take damage.
2. Leaves and stems begin to turn yellow
One of the first signs of overwatering tomato plants show is that the leaves begin to turn yellow. When it becomes more severe, the stems might also start turning yellow. It happens because there is not enough oxygen in the soil since there is too much water.
There are many reasons why the leaves and stems on your tomato plants can turn yellow, but a common reason is overwatering. If your tomato plants have yellowing leaves, look for some of the other signs on this list to be sure.
3. The top of the soil never fully dries up
Tomato plants grow best in soil that is moist but not too wet and also not dry. It can be a tricky balance to find and it can be tempting to water your tomatoes a bit extra to make sure they get enough. I’ve certainly done that before.
It is important that you allow the top of the soil to dry out before you water your tomatoes. Otherwise, it can very easily be too much water for the roots to keep up and they will eventually start rotting. which can lead to the next sign.
4. Mold appears on the soil, leaves, stems, or fruit
Mold is a common sign that a plant has been overwatered for a while. Overwatering leads to humid conditions and humid conditions lead to mold, which can appear on the soil but also on the leaves, stems, and fruit of your tomato plants. It can also appear when the roots begin rotting after being overwatered for a while.
Improving the airflow around and between your tomato plants can reduce the risk of mold.
5. The plant begins to wilt
Wilting is one of the first and most important signs to look out for if you suspect that your tomatoes are being overwatered. Tomato plants can wilt for many reasons, but overwatering is a common one and if you also see some of the other signs from this list on your plants, there is a chance you are overwatering them.
Wilting can be tricky because you can very easily think that the plants are thirsty and need more water. I’ve been tricked by that before but learned that you often need to look out for some of the other signs as well. Especially the one about the top of the soil drying up that I mentioned above (number 3).
6. Foul odor from rotting roots
When your tomatoes have been overwatered for a while, the roots will begin to rot. This is potentially critical because if too many of the roots rot, the plant dies. If only some of the roots rot, you can usually still save the plant. I explain some tricks you can use to save your overwatered tomatoes in just a bit.
If the soil gives off a foul odor, there is, unfortunately, a good chance that the roots are rotting, which means you have to act fast. If this is the case for you, skip a bit ahead to see my tips for saving overwatered tomatoes.
7. Some of the fruit is cracking open
Tomatoes can grow really fast when they get a lot of water at once since they have such a high water content. Unfortunately, too much water at once can cause them to grow so fast that their skin can’t keep up and cracks open, which makes them more exposed to pests and diseases.
It doesn’t necessarily mean that you are overwatering your tomatoes if it happens one or a few times, but if it keeps happening, you are most likely watering them too heavily.
8. Some of the leaves are curling up
A common sign that your tomato plants have a problem is that the leaves start to curl up. Overwatering is a common reason but not the only reason. If overwatering is the problem for your plants, they will most likely also show some of the other signs from this list to some degree.
9. Stunted growth
The last sign of overwatering I want to cover is stunted growth, which tends to happen when tomato plants have been overwatered for a while. I cover this sign last since it usually happens as a result of some or all the other signs on this list, but keep in mind that tomato plants also might stop growing for other reasons.
For example, some tomato plants tend to stop growing, or at least grow slower, when they are flowering. If your tomato plants are flowering, you can read this article to learn why it is happening and what you should do. Keep in mind that tomatoes can be flowering and overwatered at the same time, so see if your plants are also showing some of the other signs from this list.
Overwatering can be critical and will kill your tomatoes if you don’t do something about it. Luckily, there are several things you can do about it and you can actually often save your tomatoes if you know what to do. That’s exactly what I will cover now, so keep reading to learn how to save your overwatered tomatoes.
How to Save Overwatered Tomato Plants (8 Easy Things to Try)
If you don’t know what to do when your tomato plants are overwatered, chances are you are going to lose the plants and any fruit they would otherwise produce. You definitely don’t want that to happen and neither do I, which is why I’ve made a list of eight easy things you can do to hopefully save your overwatered tomatoes.
Of course, the first thing you have to do is to water your tomato plants less than you are doing now, but there are several other things I highly recommend that you also do.
Some of the tips in the list are for potted tomatoes and some for tomatoes that grow in the ground, but most of them are relevant no matter how you grow your tomatoes. Just try the ones that make sense to you.
1. Remove dead growth to prevent problems from spreading
As I explained earlier in this article, one of the first things that happen when tomato plants are overwatered is that leaves and sometimes stems begin to turn yellow. This happens because they are dying. When they die fully, they will be brown.
It is important that you remove any leaves or stems that are dead or turning brown from your overwatered tomatoes since leaving them on the plant significantly increases the risk of mold, pests, and diseases from targeting the plant.
2. Allow the top of the soil to become dry before you water
The root cause of tomatoes being overwatered is, as the word indicates, that they get too much water. The solution to that is to give them less (who would have thought). A good rule of thumb is to wait until the top of the soil becomes dry before you give them more water. Don’t wait much longer than that, though, since the soil shouldn’t dry up fully.
3. Make sure the soil drains properly
Proper drainage is crucial for tomatoes. If the water can’t run through the soil, it will stay around the roots until they rot.
Make sure your tomatoes are growing in sandy but nutrient-rich soil. The sand helps create better drainage. If there is too much clay in the soil, it will retain the water for a lot longer than sandy soil, which can cause damage to the roots. It might be necessary to move your tomatoes to another pot to give them better soil, which is my next point.
4. Transplant your tomatoes into another pot or the ground
Whether your tomatoes are growing in the ground or in pots, transplanting them into another pot or to another place in the ground can sometimes be a good idea to save them from overwatering.
If your tomatoes are growing in pots, carefully lift them out by holding them at the base of the stems and transfer them to another pot that you have prepared with fresh soil.
Don’t try to remove the wet soil from the roots if you do this. I once talked to one of the gardeners at one of my favorite garden centers about this specific thing and he told me very clearly, that trying to remove soil from the roots of a plant that you are transplanting will almost always do more damage than good. Instead, just move it into another pot and supply it with some dry soil as it will quickly absorb any excess water from the wet soil.
If your tomatoes are growing in the ground, it can be a good idea to move them somewhere with better draining soil (as I explained above) or more sunlight, which is my next point.
5. Move your tomatoes to a sunnier spot
The more sunlight your tomato plants are getting, the more water they use. So if your tomatoes aren’t getting as much sun as they could, moving them somewhere with more sun can be a great way to make them use more water and thereby reduce the risk of overwatering.
6. Remove the plate to allow excess water to escape
For potted tomatoes, a quick thing you can do is to remove the plates underneath the pots to allow any excess water inside the pots to escape through the drainage holes more easily. If your pots don’t have drainage holes, the risk of overwatering is much higher. If that is the case for you, I recommend that you get some clay pots (I like terra cotta) with drainage holes since they provide excellent drainage.
7. Remove mulch from around the plants
If you use mulch on the soil around your tomato plants, consider removing it. At least for now. Mulch can help retain moisture in the soil, which is usually a good thing, but if your tomatoes have been overwatered, it certainly isn’t.
Remove mulch from around your overwatered tomatoes to allow the top of the soil to dry up faster. Consider putting the mulch back after some time when the plants are good again since there are several benefits to using mulch.
8. Take cuttings and grow them as new tomato plants
Whether you do it as a last resort to save your tomato plants or simply to get more of them, taking cuttings and growing them as new plants is a great way to do it.
When you take cuttings from a tomato plant, the new plants you grow from the cuttings are essentially clones of the plant you took them from, so it can be a great way to save an overwatered tomato plant and get more tomatoes. I have a guide with photos of everything you need to do to grow tomato plants from cuttings. You can find it on this link.
Now that you know how you can often save overwatered tomatoes, the next step is to learn how to avoid overwatering them in the first place. That’s the last thing I cover in this article, so keep reading to learn my seven tips that can help you avoid overwatering your tomatoes.
7 Simple Tips to Help You Avoid Overwatering Tomatoes
Overwatering is a problem most gardeners run into every now and then, but if you know the tips I’m about to share with you, you have much better chances of avoiding overwatering your tomatoes.
I have come up with seven easy but very effective tips you can use to significantly reduce the risk that your tomato plants become overwatered.
I have learned some of the tips by talking to other gardeners, primarily employees at various garden centers and plant nurseries, and some of them by reading books and online. I do everything I’m about to teach you with my own tomatoes and it works very well.
1. Plant your tomatoes deep in the ground
If you are growing indeterminate tomatoes (the kind that grows like a vine), perhaps the best thing you can do to avoid overwatering them is to plant them deep in the ground. If you are not sure what type of tomatoes you have, you can read this guide to help you find out.
Here’s why planting tomatoes deep is a good way to reduce the risk of overwatering.
Indeterminate tomato plants can grow roots all along the stem, but only if it is underground. So the more stem is underground, the larger and more comprehensive the root system will be. The larger and more comprehensive a root system is, the more it takes for the plant to become overwatered since there are more roots to obtain water.
The best way to do this is to sow the tomato plant in a pot and once it becomes about 2 feet (about 61 cm) tall, remove the leaves from the bottom half and plant it in the ground so that the bottom half of the plant is covered with soil and the other half (still with leaves) is above ground. I have a full guild with photos and an explanation of every step on this link.
Other than reducing the risk of overwatering, the larger root system also makes the plant itself grow much better and produce more fruit. You can read more about how this works and how deep you should plant your tomatoes on this link.
2. Don’t water until the top of the soil becomes dry
A very common reason why people overwater their tomato plants is that they water them on a schedule instead of when the plants actually need it.
Watering on a schedule might be easier, but there is no universal watering schedule for tomatoes since it depends on so many things including how large the plant is, how large the root system is, the soil it is growing in, the weather, and a lot more.
Instead of having to think about all of that, I have a simple trick you can use to see when your tomatoes need water.
The easiest way to tell if your tomato plants need to be watered is to look at the top of the soil. The top of the soil should become dry between waterings, but don’t wait too long since some of the soil has to stay moist. Poke a finger a few inches into the soil and if it comes out dry, water your tomatoes.
3. Grow your tomatoes in terra cotta pots
A common mistake people make when they grow tomatoes (and other vegetables for that matter) in pots is that they use plastic pots or buckets with no drainage holes. If you do that, the water has no way of escaping other than being obtained by the roots, so if you water the plant too much, the water will stay there for a long time, which will eventually cause the roots to rot.
I highly recommend using unglazed clay pots with one or more drainage holes at the bottom. I use terra cotta pots (which is a clay-based, unglazed ceramic). Other than the drainage hole at the bottom, the material is very “breathable” and allows moisture to escape through the sides of the pot. Using these pots is one of the best things you can do to prevent overwatering.
4. Water your potted tomatoes from the bottom
This tip only works for potted tomatoes, so if you grow yours in the ground, just skip this one. It also requires pots with drainage holes, but as I wrote above, drainage holes are very important for potted tomatoes.
Watering your tomatoes from the bottom by pouring water into the plate or tray underneath the pot so that it is soaked up through the drainage hole promotes root growth. This is because the roots are encouraged to stretch to reach the water near the bottom of the pot, which they don’t have to if you water from the top. You can read more about that here.
A larger root system reduces the risk of overwatering since the plant can obtain more water before getting too much.
5. Grow your tomatoes in sandy but nutrient-rich soil
Well-draining soil is very important for tomatoes. If the soil is too dense, for example, if it contains too much clay, it retains the water for a long time, which can cause damage to the roots.
Grow your tomatoes in sandy soil since it has good drainage. It is also important that the soil is nutrient-rich and contains a lot of organic material. Regular potting soil is often good enough.
6. Make sure there is good airflow around your tomato plants
Good airflow helps the soil become dry faster and thereby reduces the risk of overwatering. It also significantly reduces the risk of other problems such as mold.
The best thing you can do to ensure good airflow around your tomato plants is to give them the space they need. You can read about that on this link, where I also share some other tips that are good to know when planting tomatoes.
7. Place your tomato plants in full sun
The more sunlight your tomato plants are getting, the more water they use, and with high amounts of both sunlight and water, the plants grow faster and get larger.
The fact that plants that get a lot of sunlight use a lot of water means that the risk of overwatering is significantly lower if your tomato plants are getting a lot of sunlight. Keep that in mind next time you plant tomatoes.