How to Water Tomato Plants: From Seedbed to Harvest

Updated: October 29, 2022

Watering tomato plants is an essential part of tomato plant care. But you can only confirm fresh, healthy, and juicy tomatoes if you only supply water by knowing the proper watering system.

Tomato plants are susceptible to contact with water. Lack of water, irregular watering, and over watering all the actions can create a threat to your tomato plants.

If you are a beginner tomato grower, you need to know the basics of watering tomatoes to become a successful gardener.

How to Water Tomato Plants

Tomato watering tips and techniques

Release water slowly and deeply to develop a robust root system for tomato plants. Let the water soak into the soil as deeply as possible. The heavy flow of water can float away from the soil nutrients.

Water your plants when they need it. To do that, check soil moisture with your finger or use a soil moisture meter before and after watering tomato plants. A soil moisture meter helps determine when your tomato plants are ready for a drink.

Watering around the bottom of the tomato plants avoids direct watering the plant’s foliage, stems, and fruits. In addition, water over the tomato plants can transmit diseases from one plant to another.

Early morning irrigation can reduce evaporation, and the tomato plants get enough time to absorb water from the soil. Soaker hoses, DIY bottle irrigation, and drip irrigation methods of watering allow you to apply water at any part of the daytime.

Avoid watering at midday due to the high evaporation of water. And never try to water after the evening when moisture and soil temperature gradually go down. Watering at night is also susceptible to some diseases.

5 significant facts to consider before growing and watering tomatoes:

1. Planting zone:

Tomato plants favor warm weather conditions to grow and thrive. As a matter of fact, planting zones have different weather conditions, including cooler zone to heat zone. It also differs due to the varying lengths of seasons.

So you have to apply different watering methods for your tomato plants according to your planting zone. Hot and dry weather zone needs more water supplies comparing cooler zones.

2. Tomato varieties:

Each planting zone introduces different tomato varieties that best suit their specific plant hardiness zone.

Some tomato varieties are heat tolerant, and some are suitable for cold climates. So, water your tomato plants based on the types you choose.

Besides, indeterminate tomato varieties need watering until the end of the season. On the other hand, determinate tomato varieties produce fruits all at once, so they need watering up to ripen.

3. Sunlight and wind exposure:

How much sunlight your tomato plants receive on a particular day is essential to measure how much water they need. Usually, tomato plants need 6-8 hours of direct sunlight to show better performance.

Tomato plants in windy weather conditions need more water supply than average.

4. Microclimate:

Suppose your gardening zone is situated in a microclimate area. In that case, you may get some benefits or face obstacles to applying water.

A microclimate area is a mini-climate zone inside a significant climate that doesn’t behave like a large climate.

A microclimate area depends on geographic location, soil structure, nearest open water sources, surrounding vegetation area, artificial structures, and hill tracks.

5. Fertilization:

Tomato plants need proper fertilization with an accurate water supply to get a better result. Therefore, you can only expect a good harvest if you supply water to the plants.

Lack of nutrients may occur yellow leaves problems, blossom end rot, or cat-facing fruit problems in tomato plants.

Watering tomatoes are easier than you think, but a matter of knowledge and practice.

Continue reading this article to get a clear concept of how to water your tomato plants the right way.

Types of irrigation:

There have two main ways you can supply water to your tomato plants.

Natural irrigation:

Rainfed farming is the natural way of irrigation for your garden plants. But in dry weather conditions, rainwater is not available.

Besides, it doesn’t cover indoor tomato plants, potting tomatoes, balcony tomatoes, and greenhouse tomato plants.

Artificial irrigation:

Tomato plants need scheduled watering, which can only be served partially through rainwater. So you need to provide extra irrigation.

Some artificial irrigation methods exist, but drip irrigation, DIY plastic bottle irrigation, and soaker hose watering are suitable for tomato plants.

Methods of watering tomatoes:

The watering tomato plant is sensitive, and there are several ways to do this. Here I discuss some practical ways to water home garden tomato plants.

Underground self-bottle watering:

Underground Self Watering Bottle System DIY

When you are finally going to transplant tomato plants, put a plastic bottle inside the hole dug up for the tomato plants. Drill holes surround the bottle so that the plants can soak the water from the soil as required.

Fill the bottle with water or necessary nutrient solutions. This system reduces water loss and protects your plants from unexpected diseases.

Deep root watering through the PVC pipe and plastic bottle:

Tomato plants deep root watering through PVC pipe diy

You can also put a two-foot and 1-inch diameter PVC pipe into each hole of tomato plants at least 6-12 inches deep. Drill some spots around the part of the PVC pipe which will remain under the soil.

Cut the bottom of a plastic bottle and attach it upside down to the surface end of the PVC pipe. This bottle will work like a funnel.

Pour water into the bottle, and the water will directly reach the plant roots. This method helps the plants get water from the deep without wasting it.

Plastic bottle drip water irrigation:

Plastic bottle drip water irrigation

This method is straightforward to provide water to your tomato plants. But first, you need one or two sticks to hang up the plastic bottle close to the plants.

Create a tiny hole at the bottom of the hanging bottle to drip water slowly near the plant roots.

Irrigation with garden cone watering spike:

Irrigation with garden cone watering spike

This is one of the easiest ways of drip irrigation. Replace soda or any plastic bottle caps with a cone watering spike and push it inside the soil near the tomato plants.

You can also control the water flow using the key attached to the watering spike.

Search your local gardening store or online shops for this watering spike.

Drip Irrigation with hoses:

Tomato drip irrigation with hoses

Installing a drip irrigation system with hoses is comparatively more costly than DIY bottle watering methods. But the good side is you can go for a more extended vacation by setting up a timer on it.

Furrow irrigation:

Furrow irrigation

Low initial investment in equipment but high labor cost. Maintenance of the system is time-consuming and sensitive.

Watering through tomato crater:

Watering through tomato crater

This device can make your garden work easier and increase your harvest. It helps too,

Hold soil moisture for a more extended period,
Stop growing weeds near tomato plants,
Protect plants from cutworms and some soil-borne diseases.

It will cost a few bucks but support your plants for a couple of seasons.

When to water tomatoes, morning or evening?

When to water tomatoes morning or evening

Morning is the best time for watering tomatoes due to some reasons. Such as:

It reduces the evaporation rate of water, and tomato plants get enough time to dry out quickly before the temperature gets cold in the evening.

Watering tomatoes at night can create a chance of overwatering. Because nighttime temperatures are comparatively cooler than daytime, and less water evaporates from the soil.

Plant leaves open their cells at night to drink naturally from the dew drops. So any supplementary water supply can hamper their inherited system of collecting water from nature.

Besides, plant roots receive water more effectively in the morning than in other parts of the day, especially after the evening.

Watering plants in the evening encourage fungal pathogens and susceptibility to some diseases.

How much water do your tomato plants need?

Tomato plants need a different amount of water in various stages of plant growth.

Watering at tomato seedlings:

They need as little as 1/4 cup of water but are very frequent. You need to monitor the soil twice a day to supply the water.

Seedlings are typically nurtured in seed trays or small pots. Using a hand sprayer is the best solution for watering seedlings.

Don’t let the seedlings remain in a puddle of water.

Make sure your seedlings receive enough air flow and direct sunlight.

Gradually your seedlings shall sprout and consume more water. Therefore, increase the supply of water as your plants’ demand.

If you notice that soil drying out in less than 24 hours and the third set of leaves appears on tomato seedlings, transplant them into larger seed trays.

Keep watering the tomato seedlings until they are transplanted into the outdoor garden.

Watering tomatoes when planting and after transplanting:

The seedlings are ready to transplant when they are six weeks old, and the seedling height reaches around 6 to 10 inches. And, of course, transplant your seedling two weeks after the last frost date.

The best time to transplant your seedlings is in the afternoon.
Before an hour of planting, water your tomato plants deeply.
After digging up the holes for the seedlings, mix the necessary compost with the soil and add some water.
When finished transplanting, slowly provide a gallon of water around the bottom of the plants to let the soil absorb it deeply.
From day 1 to 10, provide a quart of water for each plant daily. Check your newly transplanted tomato plants twice daily and offer more water if needed due to hot weather conditions.
From day 10 to 14, give each plant 1 inch of water if the weather is cool and up to 3 inches if the temperature is hot.
After 14 days, regularly check your garden soil moisture with a moisture meter and give 2 inches or two gallons of water a week.

You can increase or decrease in the water amount due to rainy days or hot temperatures. To do this perfectly, always use a soil moisture meter before and after watering.

How often do you water tomatoes?

You must consider several issues to calculate how many times you need to water your plants.

Watering consistency

Tomato plants need consistent watering more than once a week based on the temperature. Keep the plants from drying up in between the gap of watering.
Tomatoes need 1-3 inches of water every week.
Only apply a total of 1-3-inch water at a time. Instead, you can divide the total amount of water into two parts and use them every 3 to 5 days.
Just keep watering based on the demand of the plants and the weather condition.
Remember, apply at most 1 inch of water at a time when watering.
Drip irrigation is the best way of consistently watering tomato plants.

Watering tomatoes in hot weather

A mature tomato plant needs up to 3 inches or 3 gallons or 11.5 liters of water on warm days.

Check your tomato plants at midday; if they show any signs of water stress, feel free to water them immediately.

Although I recommend watering in the morning, tomato plants may need more water supply than average in hot weather conditions.

Usually, watering in the middle of the day doesn’t harm the tomatoes. But they conserve less water and evaporate more than morning irrigation.

Never try to water at night. This will not help out your plants anyway.

Watering tomatoes in cool weather

Whether the weather is cool or hot, tomato plants need consistent watering.

When the weather is cool, supply 1 inch of water a week after checking the soil moisture.

Stop watering during heavy rainfall.

A splash of rainfalls or irregular rainfalls may not fulfill the demand for water for the tomato plants.

Watering container tomato plants

Container tomato plants need regular watering due to the high evaporation rate. Container soil tends to heat up rapidly and contains little water on it.

You should start watering your container of tomatoes in the morning until it reaches the bottom of the container. And provide necessary water supply if needed later in the day.

Watering garden tomato plants

Garden tomato plants spread their roots as deep as they need to search for water. So they need slow and deep watering once or twice a week, depending on the weather conditions and temperature.

Surface and light watering systems prevent the development of a deep solid root of tomatoes.

Typically, tomato plants drink 1 to 3 inches of water each week based on the temperature (1-inch water= 1 gallon of water = 3.8 liters of water).

Watering tomatoes during fertilization

Water your tomato plants entirely before fertilization. Direct fertilization on the soil without watering can damage the plant roots and stems.

Provide light watering after fertilization as the fertilizer can easily mix with the soil, and the tomatoes can receive the necessary nutrients.

You can also water your tomato plants with a liquid solution of nutrients to feed them well.

If you apply the Bottle or Pipe watering method or use Tomato Craters, liquid nutrient watering will work much better.

Refrain from fertilizing your plants during heavy rain. It will float away the nutrients from the soil. Instead, always try to fertilize your plants after rainfall.

Watering compost tea

As an organic home gardener, you can provide a drink of compost tea once a week to your tomato plants after transplanting them.

Compost tea watering can protect your tomatoes from the attack of bad bugs and diseases.

Keep in mind, do not water the compost tea after the evening. The best time for applying compost tea is in the morning.

You can pour compost tea water directly around the bottom of tomato plants or wash your tomato plants with the tea water.

Besides, you can spray over the plants with a new sprayer. Or else, collect a sprayer that was not used as a chemical spray earlier.

Watering tomatoes by following soil types and structure

Watering tomatoes also depend on your garden soil type.

Clay soils absorb water very slowly. But once wet, it can hold soil moisture for a longer period.

So, water slowly if your garden contains clay soils. Then, make a 3-5 days gap between your following irrigation schedule, depending on the weather.

On the other hand, sandy soils absorb water quickly, but they hold moisture for a shorter time. Therefore, you have to water daily and promptly for short periods.

Common mistakes of watering tomatoes:

Beginner tomato growers usually make the following mistakes:

Watering over the tomato plants.
Watering after evening.
Deep watering before evening.
Watering at midday.
Surface or light watering of garden plants.

Overwatering tomatoes:

Too much water or too little water is harmful to tomatoes. So it is essential to know the reasons behind overwatered tomato plants and possible solutions.

Reasons for overwatering:

Lack of knowledge and technique of watering.
Poor drainage system.
Heavy rainfall.
Soil structure.
Watering at night.

Signs and symptoms:

Leaf rolling.
Leaves turn yellow.
Fruit cracking.
Encouraging soil-borne diseases like root rot.
Wilting tomato plants.
Produce watery and tasteless fruits.
Produce less or sometimes don’t set any fruit

How to recover over-watered tomato plants:

For garden tomatoes, stop watering until the soil moisture returns to an appropriate level once the plants are overwatered. Adequate wind flow in the garden can dry up the soil quickly.
For potting tomatoes, transplant them immediately to another dry pot. Remove the wet potting compost and add some dry compost to balance the soil moisture.

How to protect tomatoes from over-watering?

Arrange a proper drainage system.
Constantly water your plants in the morning.
Cover your tomato plants with a transparent plastic sheet before the rain and remove it after the rainfall.
Check the soil moisture before watering.
Only water the tomatoes when they actually need it.
Lightening the heavy clay soil by adding compost before planting.

When to stop watering tomato plants

Indeterminate tomato varieties produce fruits till the end of the season. So you have to keep watering to get tomatoes until the first frost appears.

Determinate tomato varieties and set fruits all at once. So you only need to water some of the seasons long for hybrid varieties.

Follow the exact watering method for determinate tomatoes like other tomato varieties from the beginning till setting fruits.

Once all the tomatoes set fruit and become ripening, stop watering to let the tomatoes ripen fast.

Conclusion:

Tomato watering is a matter of practice. Different amount of water is needed in different growth stages of tomatoes. So, you could not apply the same amount of water throughout the season.

Besides, tomato watering techniques, environmental effects, fertilization, and other concern issues also determine the tomato watering system.

Remember my tomato watering tips and apply them correctly to yield better.

Happy tomato gardening.

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