Watering Tomatoes: When, How Often & How Much - 5 Pro Tips

Updated on April 19, 2018
lobobrandon profile image

From his early days, Brandon helped his grandmother in her garden. He was always passionate about tomatoes.

Watering Tomatoes Is a Science and an Art

If you love gardening, you've probably already asked an expert or yourself this question: "How often should I water my tomato plants?" Don't worry, you're not alone in this quest. This guide has hundreds of people reading and sharing it each day.

Plenty of people all across the globe take to tomato cultivation, not only because tomatoes are relatively easy to grow and sustain; but the fact that they are used in plenty of different cuisines, in a variety of ways - more ways than you can imagine.

4 Facts About Tomato Growth You Need to Know:

  1. They don't grow anywhere and anytime - Tomatoes cannot be grown everywhere and not all through the year. There are plenty of tomato varieties to pick from. Speak to your local gardening club or neighbor to find out what grows best in the region.
  2. Sunlight is important - Tomato plants need sunlight in order to grow well. So, make sure that you place your plants in a sunny spot of your garden, not too hot though. Read on to know more about these settings.
  3. Nutrition - No matter how well you water, if the plants are not receiving the right nutrition, there isn't really much you can do - apart from getting this problem fixed. Check your tomato plants for yellow leaves, as this is a sign of bad nutrition.
  4. Watering tomatoes - This is definitely a skill. But, it's not rocket science and can easily be mastered. You could even teach your kids and maybe have them grow their own crop this season - it's an amazing learning experience and a chance to bond.

Pour Directly onto the Soil

When watering tomatoes never pour water on the fruit and leaves unless it's dawn or dusk. Once the sun rises, these droplets can end up burning your plant (not literally, of course)
When watering tomatoes never pour water on the fruit and leaves unless it's dawn or dusk. Once the sun rises, these droplets can end up burning your plant (not literally, of course) | Source

Before we proceed, I would like you to vote and see how often other people across the globe water their tomato plants. You could use the data to compare yourself with others and I'm sure that you will also be convinced that there is no single way to do it right.

But that's nothing to worry about, as through this article I will teach you how to find out what works best for your locality. So put on your thinking cap and buckle up! The journey begins now.

Poll: Watering Tomatoes -- What Do You Do?

How often do you water your tomatoes - It does depend on location, but do share your experience

See results

An overview of what we will be covering:

  • 5 Pro Tips on watering tomatoes
  • Rain water for your plants.
  • Caring for tomato plants when away.
  • Using enlivened water.
  • Watering tomato seedlings.
  • How often to water tomatoes?

Watering Techniques

The art of watering tomatoes is easy to master. Trial and error is one way to build up your skills. But with the right watering techniques, you can become a pro this very growing season. On following these guidelines you can also develop your very own watering techniques.

  • Water Slowly around the tomato plants allowing sufficient time for the water to enter the soil, run away water is just a waste and it steals nutrients from the soil. Let the water soak in at least 5 - 6 inches of soil.
  • Water tomatoes only when they really need it. Maybe you need to water twice a day, to begin with, just moisten the soil (don't flood the plant). The roots need air too, so don't drown your plants.
  • Water at the stem rather than the leaves. Try not to water directly on the stem of the tomato plant but around it, this encourages roots to spread.
  • Water early in the day if you use a hose, bucket or any other manual form of watering.
  • Do not water in the night as moist conditions and low temperatures increase the likelihood of tomato plant diseases.
  • Mulch acts as a moisture regulator and also a source of nutrition. Definitely give this a thought, if you don't already implement it.

Pro Tip 1: Water Slowly

The main purpose of watering your tomato plants is to ensure that they have sufficient water to sustain themselves and perform their necessary physiological activities.

Therefore, when watering, you don't want to flood the plant, only to have most of the water run off (with nutrients and top soil). Instead, you are going to need to water slowly, giving the water time to actually seep through the soil.

It is recommended that 6-8 inches below the soil is moistened when you water tomato plants as this stimulates root growth in this region, which is directly related to the amount of nutrients the plant can reach.

One thing that you could do is come up with your very own drip irrigation system. It's not at all difficult and can be done at a very cheap price - under $2, in fact! Check out the video below for a sample irrigation system. When you use a drip irrigation system you ensure that the soil is moist all the time, but not flooded - this gives the roots room to breathe.

With reference to the video below: if you don't want the bottle to hang up as shown (which can be unsightly for some) you could also place it below the soil, only keeping the opening above ground so that you could refill the bottle when needed.

Drip Irrigation System for Tomato Plants

Pro Tip 2: Water Your Tomato Plants Regularly

First off, know that there's no exact formula as to how often you should water your tomato plants. This is something that you'll need to work out based on experience. All you need to do is regularly check on the soil a few days and see when it's turning dry.

  • If you've noticed it becoming dry really quickly, don't be afraid. Instead, just try something new such as mulching or maybe a new method of watering -- drip irrigation as mentioned numerous times already works best!
  • In some regions you just need to water the plants once a day, whereas in other places you could end up watering them multiple times a day.
  • There are also a few moist areas where merely watering once or twice a week is sufficient.

If you notice your tomato plant drooping sometime around mid-day, do not worry too much about it because they will be back to normal near sunset. But if they are still drooping after sunset, this is a sign that the ground is too parched and you would need to water. But only do this the next morning. (Refer: Pro Tip 1). There are problems associated with watering tomato plants in the night. (Refer: Pro Tip 4).

Plants drooping in the sunlight isn't always because of a lack of water, it is also a reflex mechanism developed so that the plants minimize surface area in contact with the direct sunlight, which in turn reduces transpiration (loss of water from the leaves, etc.) or in simple terms evaporation.

Always water your tomato plants at the base, not from the top.
Always water your tomato plants at the base, not from the top.

Pro Tip 3: Water Tomato Plants at the Roots

If you have a habit of watering plants with a hose, it's very likely that you are also watering the leaves of the plant, instead of pointing the hose to the ground around the stem. Some of us have the tendency to water on the leaves as this makes the plants look better ;)

If by chance you do want to water on the leaves, make it a point that you water the plants early in the morning before the sun is up. If your water supply isn't pure - if it is hard water or you've mixed in fertilizer (organic or chemical) I suggest you stop watering on the leaves, as this just damages them, preventing optimal functioning and food preparation when the sun shines.

Important: Watering on the leaves and fruits increases the likelihood of tomato plant diseases. Water on the leaves at your own risk. (Refer: Pro Tip 4)

As already mentioned earlier, when I say watering at the roots, this does not necessarily mean watering directly on the ground near the stem. It's best to do it a few inches away around the stem (form a circle around the stem) as this will not wash away soil near the stem which is very important, especially if you do not have external support for your tomato plants.

You could also use Tomato Craters as seen below. They are really helpful in a sense that they let water seep into the ground slowly, you don't need to reduce the flow rate from the garden hose anymore. They also suppress the growth of weeds around the tomato plants. Moreover, they are red and reflect some of the sunlight back onto the plant which helps with photosynthesis as per some studies.

Tomato Craters help with watering tomatoes
Tomato Craters help with watering tomatoes | Source

Pro Tip 4: the Best Time to Water Tomatoes Is at Dawn

As stated earlier, watering on the leaves and fruit can increase the likelihood of some tomato plant diseases. But you may ask the dreadful question: Why!?

It's quite straightforward really, most of the tomato plant diseases are a threat under moist conditions. But this isn't the only necessary condition for the disease to foster and thrive. They also need relatively low temperatures.

So putting two and two together, it is obvious that you shouldn't water your tomato plants in the night, even if they seem droopy. When you choose to water at dawn, the plant has sufficient time to absorb water and begin the process of photosynthesis while at the same time, if by chance water fell onto the leaves, stem or fruit it would dry up before the midday sun begins to burn the plant up through these droplets.

Pro Tip 5: Mulching

In case you do not know what mulch is, it is an organic layer of leaves, hay, coconut husk, wood pieces or pine cone pieces. There are plenty of other forms too, if interested Google it. Since it's organic, it would decay over time and also be a source of nourishment for the plants.

Mulching has quite a few benefits, the main ones being:

  1. Water retention
  2. Increased room for aeration when lightly mixed with the top soil
  3. Source of nourishment

If you mulch your plants well, you're not going to need to water them as often, since the rate of evaporation from the soil is drastically reduced. So, when you mulch you may end up watering just once a day if you were previously doing it twice or more times a day.

If you don't already have mulch, you may want to check this coconut husk mulch out. It lasts for really long and is my best choice. I do not buy my mulch as coconut husk is easily available, my home being in a tropical location.

Rainwater is the best source of water for your tomato plants.
Rainwater is the best source of water for your tomato plants.

Rainwater Is the Best for Plants

Rainwater is the best for plants as it's natural and has no added chemicals during the processing stages. Moreover, if you've got hard water in your region, the salts are not the best for your tomato plants or any other plants for that matter.

If you do happen to have a rrainwaterharvesting system at home and an underground storage, one of the best ways to make use of this water is in your garden. Give it a shot and you would see improvements, if you've already been gardening for a while.

Watering Tomato Plants While on Vacation

How do I water my plans if I'm out of town? This a common question you'll come across, as we all need to go on vacation some time or another and we can't just leave our gardens to dry up. Most of us have neighbors who would be willing to help, but not all of us are that lucky.

So the best options would include:

  • Programmed Drip Irrigation Systems: These aren't expensive to install and are also very easy to operate and maintain. Therefore, if you go on vacation often or don't have the time to water your garden yourself, you could program it to water your plants everyday at a particular time. Check the video above for a simple super low budget drip irrigation system.
  • Placing plants in a basin of water: If your plants are in pots, you can always place the pots in a basin of water. Make sure that the plant is above the level of the water as you don't want to flood it. Water will enter through the exit hole, via capillary action. Make sure there is sufficient leverage between the pot and water as you do not want to flood the roots either.
  • Mulch: If you're taking a short trip (3-4 days), you could solely depend on your mulch to keep the plants alive and healthy until you return. Again this depends on the local conditions, but this is a ball park figure that works well in most cases.

Watering Tomato Plants Using Enlivened Water

Enlivened water is an ancient method wherein the water is stirred clockwise, about 40-50 times and then the plants are watered.

While it is an ancient method, modern science has backed this method, as spiraling water gains energy, since it’s in motion. Watering tomatoes with this water does make them grow healthier according to some studies.

I'm not an advocate of this method and I've not tried it out as I find it "crazy", but that's just me. Maybe you've tried it out in your garden or heard about it somewhere? If yes and you have something to say about it, please do leave a comment below.

Watering Tomato Seedlings

Watering tomato seeds and seedlings is a whole different story. Germinating tomato plants from seeds is a very simple process, but you only see the best results when done right. Since this is the first step of the tomato plants growth, you are going to want to make sure your plants get the right start.

I've already written another article on how to plant tomato plants from seeds, you may want to check it out.

When it comes to watering tomato seedlings, there is no better tutorial than this video I've just found on YouTube:

How Often to Water Tomatoes?

How often you water tomatoes is a major concern most people face, especially the first time around. It is important to have the soil moist, not flooded. The soil needs to be damp at least 6 - 8 inches below the ground to stimulate root growth. Watering once a day works best for most regions.

In case you aren't sure, begin by watering once a day and go from there. The tips above are definitely going to guide you and would help you make informed decisions rather than random guesses.

If you fail to water tomato plants the right way, it could lead to various issues:

  1. Diseases, including root loss, blossom end rot, and others
  2. Reduced fruit production
  3. Stunted growth
  4. Decreased resistance

It should go without saying, that knowing how to water tomato plants properly is the most important skill when it comes to growing tomato plants. Adding the right fertilizers at the right stage of growth is probably the second most important, else you would have foliage and not many fruits.

How Much Water Does a Tomato Plant Need

According to the article published on the website of the Ohio State University [source], tomato plants in the garden require in general 1 to 1.5 inches of water per week. But how much is 1 inch of water in gardening terms? This is by far not a standard unit of measure. This is what it means: you're going to need 1 to 1.5 inches of water in a square foot of soil.

A square foot of soil is 12 inches by 12 inches which makes it 144 square inches and the volume would be 1-inch times 144 square inches which is 144 cubic inches to 1.5 inches times 144 square inches which is 216 cubic inches.

But how much water does this convert into? Using this calculator the values I get are 0.62 gallons (2.27 liters) to 0.94 gallons (3.56 liters). I use another simple calculator to convert gallons to liters. Check out the video below to better understand this concept. In hot weather, it is more important that you water regularly.

I bet you're now wondering how much water do they need per day. This is a hard question to answer. Do we just divide the above by 7 days? It does make sense and that's roughly the amount I water my plants. Of course, I didn't begin my measuring. The amount I water is based on my own experiences and the conditions my plants grow in. You could probably begin by dividing the weekly amount to count for seven days and adjust from there.

How Often Do You Water Tomatoes in Containers or Pots?

If you're not certain on how to water tomato plants grown in pots, this is the section for you. First and foremost, I hope your pots or containers have drainage holes. If not, you're going to want to change the pot, else you'd have to be extra careful with watering to make sure that the soil is not too moist or too dry by manually checking it every day.

The thing to keep in mind with pots and containers is the fact that they cannot retain water, so all you should do is moisten the soil. You're going to want to make sure that you do not pour too much water as the excess that drains out also carries with it some essential nutrients. I personally choose to water plants in containers twice a day, once at dawn wetting up the entire soil and once in the evening (just a bit) especially during fruiting as failure to do this could lead to the tomatoes cracking open. Tomatoes crack open when the plant gets water suddenly after a brief dry period.

Questions & Answers

    Any tips or questions on watering tomatoes are welcome

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      • lobobrandon profile image

        Brandon Lobo 2 days ago

        That's interesting. Sad about the blossom end rot issues you face. But I guess you learn from your mistakes. Do you still grow tomatoes in containers?

      • RedElf profile image

        RedElf 4 days ago from Canada

        Awesome and thorough! An excellent example of an authoritative article - I have bookmarked it for future reference.

        My last home had very sandy soil, and we had to water twice a day. Those red 'tomato craters' would have been a helpful addition. One very dry year we had a real problem with blossom-end rot, caused by erratic watering. My bad - we kept forgetting to water in the morning, would get home late, and then leave the poor plants for yet another day. Not good crop that year.

        I only grow things in containers in my new home. And they have to be fast growers as our season up here is very short.

        Thanks for all the great info.

      • lobobrandon profile image

        Brandon Lobo 4 weeks ago

        Hi Texasplanter, I would remove them from their current pot slowly making sure the soil and roots are intact. Dig pits in the planter and place them there. Mulch goes on top of the soil. But mixing some in with the soil before you place the plants would also add as fertilizer. Good luck

      • profile image

        Texasplanter 4 weeks ago

        Hello ,I’m very new to planting Tomatoes. I just bought some at a local store and they are in small square placstic pots . I want to transfer them to a long rectangle planter I have will this damage them?i read how to water them and they need sunlight but how do I put my mulch on them does it go on top or inside the hole? This is a project my grandson and I are doing so I want to see good results. They will be in a planter on my porch . Thanks for the help!

      • lobobrandon profile image

        Brandon Lobo 7 months ago

        Hey Jim, I did say very clearly that I'm not an advocate for the method. But a complete article on any subject needs to include everything and that's what I have done.

      • lobobrandon profile image

        Brandon Lobo 8 months ago

        You need to make sure the roots find some water if they go looking for it. It's best to water a bit every day if you're not sure. Just don't over water. The lower portion of the soil retains water for longer so roots would naturally grow there. But if you live in a wet region, you could try what you suggested.

      • profile image

        Bob t 8 months ago

        Is watering tomatos on odd days be best to make roots "look" for water?

      • profile image

        Elaine 8 months ago

        What is opinion on watering from the bottom?

      • profile image

        Gene 8 months ago

        Really well-written. Very informative. thank you.

      • profile image

        Totally Tomato 10 months ago

        I think squirrels are eating my tomato. any advice?

      • profile image

        Jerry Eskoff 10 months ago

        Thanks for the info very helpful. In the fall I add leaves and grass clippings and rototil the soil. I have been adding worms they seem to fertilize and loosen the soil. Question; do they deleted nutrients or add that benefit the soil!

      • lobobrandon profile image

        Brandon Lobo 17 months ago

        Hi Jackie, that's amazing! Tomatoes generally crack when the fruit has grown completely and the plant receives more water than required. It could be after a heavy rainfall or just you watering them after a dry spell. It's not a disease or something to worry about. Just make sure that you pluck the cracked ones and use them to make some sauce or salsa. Also, if you notice the tomatoes are grown and you hear of a heavy downpour approaching, go ahead and pluck the ripe and semi ripe tomatoes, they don't taste that good if you pluck them after they've absorbed all that extra water.

      • profile image

        jackie 17 months ago

        what causes tomatoes on the vine to crack. they seem healthy otherwise, we have more than a 100 on two plants. seriously.

      • lobobrandon profile image

        Brandon Lobo 22 months ago

        Hi Susan, that's really interesting. I should look into that and I would definitely add it to the article. Thanks again.

      • profile image

        Susan Gates 22 months ago

        I would like to add that my husband and I use a moisture meter on our new plantings. They don't cost much and take out a lot of the guess work out of watering.

      • lobobrandon profile image

        Brandon Lobo 22 months ago

        Thanks word55. Glad you liked it

      • word55 profile image

        Word 22 months ago from Chicago

        This is very helpful. Thank you for the guide to raising tomatoes. God bless!

      • lobobrandon profile image

        Brandon Lobo 2 years ago

        Go to www.imgur.com and upload the image and post the link here

      • profile image

        Rice 2 years ago

        I have something odd going on with my tomato plants.

        The veins are really dark, nearly black.

        And my plants don't seem to be growing that fast.

        Any idea?

        Is there a place I can post a picture?

        I googled the problem and the only thing I found is that I may be over-watering.

      • possum lover profile image

        possum lover 4 years ago from the backwoods just to the North of South Carolina

        That's a good looking tomato in your photo, and I'm sure it was delicious when it was time to eat it!

      • profile image

        deming_jim@yahoo.com 4 years ago

        I live in Bakersfield, CA. Hot and low humidity. I was told yesterday to back off on my twice a day watering so thee fruit would grow. (one of my plants is over 4' tall. I have lots of blossoms, so far, not a lot of fruit.

      • lobobrandon profile image

        Brandon Lobo 4 years ago

        Hi Denis, that's really cool if you use water from your well. Tomato plants and all plants in general would surely love some pure water rather than the treated water we usually receive through our taps.

      • sdenis profile image

        Denis Sakac 4 years ago from Croatia

        This is really useful hub.I have garden and we use water from the well.

      • lobobrandon profile image

        Brandon Lobo 4 years ago

        The mulch I've always used is just coconut husks or hay, haven't tried anything in specific because the nutrients that are needed for the tomatoes are already present in the compost added.

        But, for tomatoes something acidic would be fine and they'd possibly grow well. If you do try it out let me know.

      • Wimberlyj profile image

        Stephen John Wimberly 4 years ago from Mount Dora, Florida

        Your mulching comment has me interested. What would be the 'ideal' mulch for tomatoes? Something acidic I would assume?

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        Hi Marlin, since you say the air is humid, you could water them once every two days or so. But, some times, even though the air is humid, the soil tends to dry up fast. In such cases you would need to water daily. When you water them, just sprinkle some water rather than flooding the soil. Yellow leaves could be caused in many ways including excess watering as well as simple aging of the leaves. Check this out for help regarding yellow tomato leaves - https://dengarden.com/gardening/Yellow-leaves-on-t...

      • profile image

        mariInGA 5 years ago

        Any tips on watering in hot humid weather? I am in GA and so far, so good, with the tomatoes. They are all still green but one plant's leaves are turning yellow. I water once a day -- surely not too much?? Any tips??

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        That's great! I'm sure you'll get a great crop if you take care of the plants.

      • Pinkchic18 profile image

        Sarah Carlsley 5 years ago from Minnesota

        Thanks for the help and advice! We planted 10 tomato plants this year, and are hoping for good crops :)

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        Wow! That's more than double my age :) I'm sure you'll be an expert by now. Would love to read some of your hubs if you do write any on this topic. And getting this from you is really a compliment. Thanks so much Joaniebaby.

      • joaniebaby profile image

        joaniebaby 5 years ago

        We have grown tomatoes for over forty years and have always just let them grow and hope for the best. Usually that works out pretty well, but not always. I am definitely going to watch my watering this year and see what happens. Thanks for the useful Hub.

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        Oh I didn't know that the temperatures fall that low in Central Europe Lithuania in particular. Glad that you added this info to the hub - Thanks :)

        In frosty areas you'd have to be careful while watering - I mean the time of the day.

      • profile image

        AndriyR 5 years ago

        Nice hub! Tomatoes are really very tender plants: here in Central Europe they are mostly grown in warm houses because on the open area they can easily get frosted (sometimes at night the temperature here can fall below 0 C). That is why, good watering is also important to keep the soil a little warmer.

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        The addition of Earthworms was just advice from a person who loves gardening - Me :) It's not exactly a part of watering tomato plants, but earthworms are usually present in ground soil.

      • Jojosi profile image

        Gillian Namele 5 years ago from Complicated

        I agree completely. Drip irrigation takes care of water-logging the plants, which tomato plants hate so much. As for the addition of earth worms- uuh? Great info, voted up.

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        Haha :) I find earthworms to be a great help. If you've taken the soil from your garden, I'm pretty sure there'll be some in it already.

      • ktrapp profile image

        Kristin Trapp 5 years ago from Illinois

        I am pretty sure earthworms may be where I draw the line. I guess that makes me not a true gardener, but I do have my limits. haha.

      • lobobrandon profile image

        Brandon Lobo 5 years ago

        Yes, mulch is a great way to retain moisture, since you planted them in a container, if possible try adding some earthworms to the soil too. They really help a lot. I wish you luck with your tomatoes, I'm sure they'll do well :)

      • ktrapp profile image

        Kristin Trapp 5 years ago from Illinois

        This is very timely information for me since I just planted some tomatoes. I planted them in a container and I may consider adding a small amount of mulch if that will help keep the moisture in.

      • lobobrandon profile image

        Brandon Lobo 6 years ago

        Hi again Hazel ;) I'm sure those tomatoes would be amazing and delicious. Thanks for sharing your own experiences :D

      • hazelwood4 profile image

        hazelwood4 6 years ago from Owensboro, Kentucky

        This is some very useful information on watering tomato plants. My dad used to grow some huge tomatoes here in Kentucky. The plants were called Big Boy Tomato plants. The fresh tomatoes were so scrumptious. Thank you for sharing!

      • lobobrandon profile image

        Brandon Lobo 6 years ago

        Great! Just a bit of experience and research helped me through :). Btw these tips work for almost all plants and not just for watering tomatoes.

      • lobobrandon profile image

        Brandon Lobo 6 years ago

        Hi Robie, Thanks for the comment as well as appreciation ;)

      • North Wind profile image

        North Wind 6 years ago from The World (for now)

        I love to plant tomatoes but I don't think I water them right so your tips will help a lot. Thank you.

      • Robie Benve profile image

        Robie Benve 6 years ago from Ohio

        Great advice, thanks!