Watering Tomatoes: How much Water do Tomato Plants Need?

Tomatoes are among the common vegetables grown in our gardens. This is attributed to the fact that they are relatively easy to care for and maintain. Watering is among the crucial care that tomato plants require throughout the season.

The amount of water a tomato plant needs is determined by various factors like the stage of growth, the type of soil, and the weather conditions. Tomato plants require little water and frequent watering during the seedling stage. The amount of water is increased gradually as the plant matures. 

Slow watering is recommended when the plant begins to fruit. Too much water causes cracking and splitting in tomato fruits.

How much water do tomato plants need?

To maintain a healthy tomato plant, there must be even and constant moisture in the soil. This means that the water is not supposed to be inadequate or excessive.  Insufficient water in the soil causes the plant to have stunted growth, wilt, and die. 

On the other hand, excess water in the soil can cause diseases like blossom end rot in tomatoes.

Various factors determine the frequency and amount of water a tomato plant needs. Some of them include the following:

1. Stage of growth or depth of roots

Tomato plant water needs increase with the growth and reach the peak when flowers and fruits start to appear. This means that you will require watering your seedling with little water and increase the ratio and frequency gradually as they mature.

When you start to germinate your tomato seeds, it is important to check the moisture content in the soil. The soil may dry up quickly when the seedlings are in small trays or containers. Generally, the seedlings require little water, and the need increases when they grow. 

When the seedlings are transplanted in the garden, their roots will start to grow deeper into the soil in search of water and anchorage. During this stage, your watering intervals are supposed to be increased and a larger amount applied per application. 

It is also important to be cautious when watering your tomato plants, especially when they start flowering and fruiting. Water at the base of the plant and not on the foliage. Watering on the leaves and fruits can lead to tomato sunscald. 

2. Weather factors (Temperature, sunlight, humidity, and wind)

Tomato plants require warm temperatures. In such conditions, the rate of water evaporation from the plant and soil is high. Also, the plant uses more water when it is hot. Therefore, it is important to water your plants twice or more when it is hot.

The plant requires more water when it is sunny as compared to when it is cloudy. When mulch is not applied in your tomato garden, the soil will also lose more water when the weather is sunny.  This also happens in windy weather conditions. 

How will relative humidity affect your tomato plant’s water needs? When humidity decreases in the air, the plant uses more water, and the rate of evaporation increases.

3. The type of your soil

The type of soil in your garden also determines the amount of water you will use on your tomato plants. The water-holding capacity of the soil largely depends on its texture. For instance, sandy soil tends to lose more water than clay soil due to its large pore spaces.

If you are staying in an area with sandy soil, try to add humus content to the soil to improve its water-holding capacity. 

Usable soil depth will also determine the amount of water your tomato plants need. Hardpans or very compacted soils may restrict the root depth. With such soil, lighter and more frequent watering is required than when the soil is less compacted. 

How to water tomato plants 

How do you ensure that your tomato plants are well watered? The best time to water your tomatoes is normally early in the morning. It allows the plant to absorb enough water before the weather becomes hot and dry. 

It is discouraged to water tomatoes in the evening. When the temperature drops at night, the water becomes too cold and hence exposes your plants to health risks. 

The yields from your tomato plants can be determined by the manner in which you are watering them. Consider watering the stem or base rather than the foliage. Watering on the leaves and fruits can cause diseases. 

There are various ways you can use to water your plants effectively. Some of them include the following:  

1. Regular watering of tomato plants

How often do you water your tomato plants? The answer to this question is determined by the type of soil in your garden, weather condition and the stage of growth of your plants. All you need to do is check the moisture content of your soil regularly to see if it is turning dry.

When the soil starts turning dry, it is time for you to water the plants. If the soil is becoming dry quickly, there are also other measures you can take to help in water retention. For instance, you can add more humus to the soil, apply mulch or install a drip irrigation system in your garden.

Depending on your region and other environmental factors, you may be required to water your tomato plants once a day, twice a day, once a week or twice a week. Wilting is not only caused by inadequate water, but can also result from pests and diseases.

2. Water at the base of tomato plants

Most tomato gardeners use a hose connected to the tap to water their plants, and the chances of watering the foliage are high. It is not a bad idea to use a horse pipe, but ensure that the nozzle is pointed at the base of the plant. 

Watering on the foliage puts the plant at risk of developing diseases like blossom end rot. The water can also damage the leaves, especially when it is hard water or when mixed with fertilizers. Employ other methods of irrigation, like drip, which delivers water right to the base. It is also easy to apply foliar fertilizers with drip irrigation. 

3. Water tomato plants early in the morning

Why water tomatoes at dawn? Tomato plants require warm temperatures, and watering at dawn ensures any droplets on the leaves dry up when the sun rises. As stated earlier, water on tomato plant foliage increases the risk of diseases. 

4. Water slowly or gently

When it comes to watering tomatoes, you have to go slow to ensure the plant gets sufficient water. Allow the water to penetrate deep into the soil. When watering, you don’t have to gush a lot of water on the plant.

Flooding the plant with water can wash away the topsoil that contains nutrients. It can also leave the roots of the plant exposed. 

Methods like drip irrigation ensure the water percolates slowly deeper into the soil. It is recommended to ensure 6-8 inches of soil is moistened. It encourages good root development in tomatoes. The plant roots will also be able to reach nutrients that are located deeper in the soil.

5. Apply mulching

If you are watering your tomatoes frequently, then it is high time to think about mulching. Using mulch helps to keep water in the soil at the level required by the plant. It also helps to reduce the rate of soil water evaporation. 

How often to water tomatoes in pots

Tomatoes planted in pots or containers may require little and frequent watering as compared to their counterparts that are grown directly in the garden. However, it is also important to ensure the pots have drainage holes to get rid of excessive water.

Containers or pots are poor at water retention. Therefore, you have to come up with ways of reducing watering. Some of them include:

1. Plant in large containers

Big pots or containers hold a large volume of soil and water. This means that they are not likely to dry quicker than those in small pots. 

2. Add humus to the potting mixture

Humus or other organic manures increase water retention. This technique works well, especially in areas with clay soil. Mix organic amendments with the soil and fill the pots before planting your tomatoes.

3. Cover the pots or choose a good container material

If your pots are exposed to direct sunlight, you may consider covering them with a material that reflects heat.  It helps to reduce the rate of soil moisture evaporation and hence retains the water.

When selecting the containers to plant tomatoes, go for plastic or metallic containers. They retain more water compared to fabric or terra cotta materials. 

4. Use self-watering pots

To help save you from a daily routine of watering your tomatoes, you can go for self-watering containers. Such containers are designed with a water reservoir at the base. It helps to water the plant by itself for a certain period of time before being refilled. 

5. Mulch the containers

Mulching is proven to reduce the rate at which moisture evaporates from the soil. However, you have to choose a mulching material that does not introduce weeds, pests, and diseases to your plants. 

Can you overwater tomato plants?

Yes, you can overwater a tomato plant. The quality of your tomato yields depends on how you water them. Inconsistent watering can result in blossom end rot. This is a condition that causes the tomato fruits to turn black at the bottom. Just like too little water, excessive water can also cause stress to your plants. 

Check the soil moisture content first, prior to watering. This can be done by inserting one or two inches of your finger into the soil. Alternatively, you can scoop some soil and feel it between your fingers. If it feels dry, it is the right time to water. 

Improving drainage in your garden can also help to ensure the plants remain healthy. If you are planting in pots, ensure it has drainage at the bottom to drain away excess water. Excess watering can also cause split or cracked tomatoes.

Improper watering in tomatoes can result in:

• Blossom end rot
• Reduced yields
• Cracked or split fruits
• Poor root development
• Stunted growth
• Low-quality fruits.

Learn more: How to save overwatered tomato plants in your garden

When to stop watering tomatoes

Slow watering is recommended when the tomato plant begins to fruit. Reduce watering, especially for the large-fruited tomato plants, when the fruits begin to ripen. It helps to concentrate the flavor and also reduces cracking and splitting of the fruit. 

Stop watering your tomatoes at the end of summer when they have stopped yielding. When winter or low temperatures set in, they will die. This signifies the end of sthe eason. 

Final Thoughts

Young tomato plants can fully recover from soil moisture stress. However, when there is a water shortage during the flowering and fruiting period, the quality and quantity of your yields are negatively affected. Knowing the right watering techniques of your plants determines your success in tomato gardening.