How Much Water Does a Tomato Plant Need Per Day?

Here is a quote you’d get the gist of easily: the road to a poor tomato harvest is paved with good watering intentions.  How much water does a tomato plant need per day?

That quote sums up the problem some tomato farmers face. Their hearts are in the right place in terms of watering their tomato gardens. They put in the time and expect, like we all do, to harvest healthy, juicy, red tomatoes at the end of the growing season. But the reality is, sadly, quite the opposite.

Most times this puzzle could simply be down to a wrong watering strategy or to be more specific, not knowing how much water to provide the tomatoes daily.

The odds that you are reading this because the above problem is your current reality is high. Today is your lucky day. This article is a comprehensive take on everything you need to know about the daily water needs of your tomatoes whether they are garden or potted tomatoes.

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How Much Water Does a Tomato Plant Need Per Day?

To be clear, there are no stone-etched rules about how much water tomatoes need daily. Watering routines are actually flexible and depend on factors such as the type of soil, temperature, humidity, age/size of the plant, and the amount of weekly rainfall.

But one unchanging rule is that for tomatoes to stay hydrated and healthy, whether they are potted or grown in the garden, the soil moisture level must be even and consistent. The primary goal at all times is to ensure the soil is evenly moist or never allowed to get dry.

With that out of the way, let’s get down to some specifics in terms of the actual amount of water to use daily for your tomatoes.

Generally, it is recommended that for each square foot of soil, the tomatoes should receive between 1 – 1.5 inches of water. For a regular gardener that deals in gallons of water instead of inches per square foot, that translates to about 220 cubic inches of water or about 1 gallon of water for every one foot per week (using 1.5 inches per week)

So, if your tomatoes garden is spread over 5 square feet, for instance, you’d need something in the region for 5 gallons of water weekly for the tomatoes.

To get how much water your tomatoes need per day, simply divide the weekly figure by 7 days. For some folks, 5 days instead of 7 is used to get the approximate amount of water daily. Keep in mind that this isn’t an exact science, but it is critical to get the right amount of water as close as possible to prevent underwatering or over-watering.

Some adjustments would be needed when it comes to seedlings and potted tomatoes though.

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Tomato seedlings :

The trick to getting it right with tomato seeds and seedlings is to constantly check (more than once daily) the moisture levels of the containers or seeding trays. The goal is a potting soil that is always moist as opposed to wet. Wet soil is a sign of over-watering.

You can use a spray can to mist seedlings several times daily to keep the soil in line with the ‘always moist’ target.

Again, how much water you spray on the seedlings would depend on factors like temperature, humidity, and airflow. If you think the soil is too wet, there are two things you could do immediately to resolve this:

  • Improve the airflow around the area the speed up drying and,
  • Stop watering the seedlings until the soil is simply moist again. Never allow it to get dry though.

Before finally transplanting the tomatoes, you should gradually reduce the amount of water to the seedlings to help them adjust to garden growing conditions.

In the first few days following transplanting of the seedlings, the watering strategy should be about watering deeply and more frequently. This is the ‘establishment’ phase so they need all the help they can get to prevent stressed, weakened plants that are susceptible to diseases and pests.

You can ease off on the watering frequency and intensity after the plants become fully established.

Potted/Container tomatoes:

Tomatoes grown in pots or containers have different needs when it comes to watering compared to garden tomatoes.

Since containers or pots heat up more quickly invariably raising the soil’s temperature faster, the rate water evaporates is higher. That should mean more water right? Not really.

Actually, you’ll need less water for each watering session compared to garden tomatoes. It is the frequency that is critical.

So instead of the standard once a day, you’d likely water your tomatoes more than once a day depending on factors such as temperature and humidity.

After watering in the morning, the recommended practice is to check on the soil in the container all day long to make sure the soil is not dry.

A quick, simple soil moisture test is to stick a finger to about 1 inch below the soil surface. If your finger comes up dry, you have to water the tomatoes again.

The Best Time to Water Your Tomatoes

For your tomatoes to grow and produce healthy fruits, the watering routine must be deliberate in terms of the right time to do it.

The recommended time to water your tomatoes is early mornings. This allows the water to get entrenched in the soil and provides enough time for the roots to move water to the leaves before the sun comes up.

With adequate watering in the morning, the tomato plants can go about the business of producing energy through photosynthesis. Typically, this takes place at almost the same time every morning and water is essential to the process.

If you have to water a second time, perhaps is because the soil is dry, wait until late afternoon or early evenings. But you should try as much as possible to restrict watering to once a day, especially for garden tomatoes.

It is vital to understand that late afternoon watering is not the same as nighttime watering. You want to avoid the cooler temperatures of the night when watering. The weather conditions at night, especially the lower temperatures, increases the chances of tomato disease outbreaks.

When to Scale Back on Watering Tomatoes

The end of the summer signifies the conclusion of the tomato growing season. At this point, the temperature begins to dip which also affects the rate of evaporation and how fast the soil dries up. You might want to reduce how much water the tomatoes get daily.

One benefit of cutting back on the amount of water is linked to the fruit ripening process. With reduced water availability and intake, the plants focus most of their energy on the fruits rather than processing water. It is safe to say that reducing water supply is a signal to the plants to concentrate their resources on getting the fruits ready for harvest.

Many tomato farmers even believe that cutting back on watering at this late stage improves the flavor of the fruits.

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Tips For Watering Your Tomatoes

Water the roots

Try as much as posing to direct the water at and around the base of the stem. Except for rainfall, overhead watering is out of the question to prevent water from touching the leaves. This can lead to diseases and pest attacks.

Water deeply and slowly

It is better not to water your plant than to rush it if you don’t have the time. When it comes to tomato watering, taking it slow and steady is very crucial. And you only stop when the water begins to pool around the stem.

If you can’t do it manually for lack of time, install a drip irrigation system or a drip hose to help deliver the water to the base of the stem slowly.

Mulch away

Mulching the soil is more about water management. The right organic mulch is a heat and moisture regulator that guarantees the soil retains water for as long as possible.

There goes the answer to how much water does a tomato plant need per day?