Under watered tomato plants exhibit various symptoms like leaf yellowing, curling up, weaker stem, poor flowering, and fragile fruiting. When you spot them, try some fixes as soon as possible, or all your efforts will be wasted.

Saving Your Underwatered Tomato Plants

Don’t worry. Lucky for you, the main underwatering symptoms and every saving method are discussed here in detail. So, stay till the end.

Symptoms of Under Watered Tomato Plants

To find whether your tomato plants are underwatered, you should first check the moisture in the soil. If it is dry, it means there is watering stress. Similarly, leaf drop, failure in flowering, poor quality fruit, and stunted growth are signs of under watered plants. 

– Bone Dry soil

Moisture-less soil is the most evident sign that your plant is not getting enough water. While the top of the soil is rarely completely moist, the potting mix should be wet at least 1 to 3 inches below the surface.

To check this, you should have a moisture meter in your gardening tool cabinet. This instrument gives the moisture rating. If it shows the soil around the root has no moisture, water your tomato plants immediately.

When you let plants stay under watered, roots won’t be able to absorb nutrients, which will impact the whole growth. Soil dryness problems can get worse if the humidity levels are low. In this situation, plants face heat stress, affecting every part.

– Leaves Drooping

Ever forgot to water tomato plants? If you do, the leaf condition will remind you about it. Leaves drooping is another big sign of an under watered plant. As mentioned above, roots don’t absorb nutrients when the soil is dry. So, a shortage of both water and essential nutrients can limit photosynthesis. As a result, plants won’t be able to make their food and will eventually weaken. 

Many people often wonder – what do under watered tomato plants look like. Well, tomato leaves will turn brown or yellowish. When you initially notice these brown or yellow leaves, you can see that the discoloration will start at the base and then extend upwards. 

Furthermore, leaf curling will also happen, which is another obvious sign that your plant is dehydrated. So, If the leaves on your tomato plant are not robust, it is begging you to water them.

– Flowering Failure

The drooping of blooming flowers is another indicator of a lack of water. It happens because of the low photosynthesis rate, which generates insufficient energy. In some cases, your tomato plant may fail to blossom at all.

Even if the flowers of an under watered tomato plant successfully bloom, most of them won’t be able to sustain. So, expect a limited yield if your plant is shedding early flowers or needs help to produce blossoms. Even if treated swiftly and correctly, this problem can result in a late harvest towards the end of summer.

– Fragile Fruit

If there is no soil moisture, the tomato fruit will be fragile. The reason is that a water shortage impacts nutrient absorption and photosynthesis. It means there will be very limited glucose, which is insufficient for proper fruiting.

Reasons for Under Watered Tomato Plants

When a tomato is fragile, it is an open invitation for flies and insects to devour and harm the fruit. Furthermore, water stress may cause dry, dark, and light brown blotches on your tomato. So, such tomatoes will not be fit for human consumption.

– Deformed Plants

The whole plant shape is affected when there is water stress. When tomato plants wilt, stems weaken, leaves curl up, and discoloration becomes visible. Note that these symptoms can happen to both under watered and overwatered tomato plants. To confirm, you should check the moisture in your soil too.

– Poor Development and Growth

When you plant tomatoes in pots from seedling trays, you are usually eager to watch them grow, develop, and produce fruit. However, when they are under water stress, their growth becomes slow.

Like many other plants and trees, tomato plants absorb nutrients and water via roots. These are the key for plants to thrive. When there is not enough water, growth will be slower than expected. Furthermore, no plant part will grow to its full potential as well. 

Let’s start with roots. Depending on the tomato variety, the average length of tomato roots is roughly 8 inches. Similarly, the stem is also around 3 feet in height. They won’t reach their potential height/length when you don’t drink enough water. So, how to revive tomato plants after being under water stress? It’s time to find out.

What Are the Best Ways to Save Under Watered Tomatoes?

The most effective way to save underwatered tomatoes is to apply sufficient water. It is also critical to improve soil drainage and remove excessive moisture to improve water uptake. If these things are not possible, then repotting is the only thing left to do to save underwatered plants. 

– Add Water Sensibly

Correct watering is one of the basics of growing plants. If you spot underwatering symptoms, the first thing to do is apply water properly and at the right time. Doing it wrong can lead to overwatering, another undesirable situation your plants don’t want to face.

You should add enough water to moisten at least two inches of soil. When doing this, use a moisture meter to check whether you have added too much water. Furthermore, it would be optimal if you watered your plants in the evening or early in the morning rather than during the day. It is because most of the water evaporates before reaching the plant roots during the daytime as heat increases. So, water tomatoes sensibly to save them from stress.

– Use the Right Equipment/Technique

It is always worth the money to invest in good watering equipment. Most people prefer water cans for watering tomatoes as they are the cheapest. If you also decide to use one, choose the rose head one as it offers the best results.

Some make the mistake of using a can that has a big mouth. With this, they overwater and displace the dirt (which washes away nutrients). But with a rose head can, the water will disperse properly into multiple smaller drops.

Solution for Under Watered Tomato Plants

If you prefer to water your plants with a hose, use a nozzle or watering wand to let the water flow slowly and softly. A soaker hose is another simple way to rinse your tomatoes at once. To water, a tomato plant with the hose, run it past the base of each plant and turn the water on.

If you have a few extra bucks, invest them for a drip irrigation setup. It is the most efficient way to provide water and nutrients to plants. You provide water and nutrients straight to the root zone whenever you want. It also ensures that each plant receives water exactly what it requires to grow faster.

Some gardeners say a sprinkler is the most convenient alternative for watering tomato plants. That’s not the case, as it is the least effective one. How? Sprinklers irrigate plants from above, which means water will fall on the leaves.

This raises the chance of some diseases and pests wreaking havoc on your tomatoes. Furthermore, the moisture evaporates quickly, depriving your plants of the water they need to grow. So, water tomato plants with good care and planning.

– Remove Stagnant Water

When you grow tomatoes indoors, one problem that usually occurs is water getting stuck in drip trays. You must remove it if you don’t want to face problems like fusarium wilt, verticillium wilt, root rot, and much more. They will have the same symptoms as under watered plants. 

You must be wondering how stagnant water causes under watered stress? This water buildup prevents the roots from absorbing, keeping your tomato under watered. This goes for outdoor plants too. Get rid of all the extra water, and then wait a few days for the soil to dry before you apply water again.

– Plants Tomatoes in Ideal Location

You should carefully choose ideal spots for growing tomatoes. There should be enough sunlight in these locations for smoother photosynthesis without water evaporation. If you grow plants on such a spot, where sunlight falls more than 8 hours, then most of the water you apply will evaporate and be of no use to the plants. Furthermore, the heat stress will also cause the leaves to dry up.

Similarly, if you are growing a potted tomato plant indoors, ensure you place grow lights at an ideal distance. Plants should not be too close to them, or else they will face stress. It’s no secret that tomato growing in a pot requires more care. So, keep an eye on the soil condition and leaves behavior to detect watering stress at an early stage.

– Re-pot Your Tomato

Watering stress can occur if you grow tomato seedlings and plants in a small pot. In small-sized pots, only very little water can be applied. During the daytime, some of it evaporates too. So, plants don’t have enough water they need. That is why you should transplant it to a bigger pot as soon as the tomato plant grows a little.

When the plant shifts to a bigger pot, the roots will have more space to stretch. You can also add more water, which is easily absorbed by a stronger root system. Ensure you don’t water deeply, as improper watering can cause fungal diseases.

Effects of Underwatering on Tomato Plants


So, now you know all the under watered tomato plants symptoms and what to do to save them.

Here are the main points that you should keep in mind:

  • When you observe bone-dry soil, moisten the top two inches straight away.
  • Always use a moisture meter to keep track of the moisture status of the soil to avoid any watering stress.
  • Use the best watering pieces of equipment and techniques for better watering.
  • When seedlings grow a little, transplant them to a bigger pot for proper water application.

So, follow every point in this guide to detect and remedy tomato plants’ water stress.

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