Having a successful tomato harvest depends heavily on your care, and you want to learn all the best techniques. You’ll quickly learn that maintaining consistent soil moisture is part of the deal, leaving you to wonder how often to water tomatoes in your garden.
You’re not the only person wondering the same thing. Tomatoes are considered easy to grow and maintain, but they are selective about proper watering.
If you don’t water your plants enough or too much, they’ll protest and exhibit signs that a problem is brewing.
So, how often should you water tomato plants?
Tomato plants need to be watered daily or every other day unless you have had recent rain. The plants need 1-1.5 inches of water per week, but container-grown tomato plants need to be watered twice per day. The best time to water your plants is early in the morning before the sun gets too hot.
It’s hard to set a rule for watering tomatoes because it does depend on your weather, but you want to make sure to get it right with trial and error. Here is what you need to know about watering your tomato plants.
How Often to Water Tomatoes
For most gardeners, especially new ones, the biggest concern about growing tomatoes is understanding how often you should water tomato plants. Like most plants, they do have specific requirements.
The soil should be kept damp 6-8 inches down in the ground around the root system to encourage proper growth. At the same time, know that there is a difference between moist and soggy. You don’t want your garden soil to be wet; that can lead to root rot or other diseases.
In most areas, watering tomato plants once a day is sufficient. If it rained recently, you could water every other day, and during periods when the temperature is higher than 90℉, you might need to water twice.
The best thing to do is start by watering once per day and see how your plants do. They quickly let you know if you’re watering too much or too little, so pay attention to your plants for hints about their needs.
How Often to Water Tomatoes in Containers
Growing tomatoes in containers is a bit different than in-ground gardening, and the same can be said for their watering needs. Here is what you should know about watering your potted tomato plants.
Signs of Improper Watering
Tomato plants exhibit signs that let gardeners know there is a water issue. Watching for these symptoms can give you a heads-up that something needs to be changed.
If you notice that your plants start to droop around mid-day, don’t stress out too much. It’s common, but what isn’t normal is when your plants are still wilting after sunset.
That is a sign that the ground is too dry and you need to water, but do that the following morning, not at night.
How Much Water Do Tomato Plants Need
The general recommendation is that tomato plants receive 1-1.5 inches of water per week.
What does that even mean for an average gardener? Most people don’t measure water by inches, so what does that mean for us.
When it comes to gardening, water recommendations are always given in inches, which can be confusing, but it essentially means that these plants need 1-1.5 inches of water per square foot of soil.
A square foot is a 12in x 12in square; you would have several of these squares around your tomato plant, depending on its size.
To make it a little easier for you, you can convert this into a gallon form, making more sense to most people. It’s good to know that there are 144 cubic inches in a square foot; you can multiply this by the water recommendation.
Need an example?
If you want to give your tomato plants 1.5 inches of water per week, that’s 1.5 inches by 144 square inches. That equals 216 cubic inches of water, totaling .93 gallons.
Most would round this up to 1 gallon per square foot, so if your plant covers 3-4 square feet, you might need to water 3-4 gallons per week.
Now, how do you figure out what that would equal per day?
Everyone is different. You might take the total amount needed and divide it by seven days. Remember, it doesn’t need to be an exact science; just try to get it as close as possible.
When Is The Best Time Of Day To Water Tomato Plants
Part of effectively watering your tomato plants is knowing when to water them.
The best time to water your tomato plants is early in the morning. Doing so is most effective because it gives your plant time to move the water into the leaves before the primary heat of the day begins.
It also prevents you from burning plants; if you water in the middle of the heat, the sun can burn your plants when water droplets sit on the leaves.
Watering in the morning uses the plant’s natural biological functions. Make sure you avoid watering in the evenings as much as you can.
Why Should You Avoid Watering At Night?
While the evening might be the most practical time for you to water your garden, the moist conditions and lower temperatures increase your plants’ likelihood of facing diseases.
When And How to Water Tomato Seedlings
Watering your tomato seedlings is a bit different than your tomato plants. They’re small, so their needs do differ a bit.
Starting tomatoes from seeds is the most cost-effective choice if you want to try different cultivars and need several plants. It’s not budget-friendly to spend $50-70 just on tomato plants!
The problem with tomato seedlings is that they are tricky to water adequately. The soil dries out fast when you use small containers or trays, and you have to take time each day to check on them.
Here are some things you should know about watering tomato seedlings.
What Water is Best for Tomato Plants
The best water you can use for tomato plants (and any plants in general) is rainwater because it’s natural and doesn’t contain any added chemicals.
If you live in a region with hard water, the salts in the water can be damaging to any plant, including tomatoes, so it’s best to either use a softening system or use rainwater.
If possible, putting together a rainwater harvesting system with storage would be ideal for your entire garden.
The Best Way to Water Tomato Plants
Watering tomato plants the right way is a skill that takes trial and error, but no one wants to damage their plants while they make those errors. Some watering techniques will help you get it right the first time without any big mistakes.
Here’s the best way to water a tomato plant.
1: Always Water The Stem
It would be best if you always watered the tomato plant’s stem rather than the leaves and flowers. That means overhead watering is out unless it’s from the rain.
You should not hold a hose over the top of your plant and water, letting it drip down. For some plants, that works, but you’re asking for disaster if you do that with tomato plants. The water must get to your plants’ root system, and the most efficient way to do so is to water around the stem.
2: Water Slowly
Don’t rush and dump a gallon of water on your plants then walk away. If you do that, most of the water will run off and be a waste, stealing nutrients as it drains away.
Instead, you want to water your plants slowly, giving it ample time to soak into the soil rather than running off. Your goal is for the water to soak into the top 5-6 inches of soil in your garden.
3: Try A Soaker Hose Irrigation System
Now that you know the root system must receive the water, it makes the most sense to use a soaker hose system rather than a traditional watering hose. Not only is it easy to damage garden plants as you move the water hose around, but it’s not as efficient at providing water to your plants’ roots.
What’s so great about a soaker hose system?
It’s a hose that you place around the stem of your plants that you keep there. Seriously – you don’t move them! You can adjust the water flow from the soaker, giving the soil time to seep into the soil. It’s the most efficient way to water plants.
4 Tips for Watering Tomatoes The Right Way
Use Mulch!
Using mulch is not just an extra idea you might consider; you need to use mulch in your vegetable garden and around your tomato plants.
Organic mulch is the ideal choice because it will decompose over time, providing additional nutrients to your soil.
You should use mulch to help with watering tomatoes because it acts as a moisture regulator.
It will help reduce evaporation and retain moisture in your soil, which means you might be able to water every other day rather than every day – that’s huge when you’re a busy gardener!
A few other benefits of mulching include:
So, what type of mulch can you use on your tomato plants? You have several great organic choices, such as:
Understand Watering Is Based On Your Climate
There is no perfect answer for how often to water your tomato plants because it’s highly dependent on the climate and weather in your particular location. Regular checks of your soil are essential if you want to water correctly.
Try A Soil Moisture Meter
You should check your soil each time before watering to be sure that the ground truly needs more water.
Scale Back As The Temperatures Dip
As the temperatures start to dip as summer comes to an end, you can scale back how much you need to water.
When the temperatures aren’t as high, the evaporation rate starts to decrease, so the soil stays moist for longer. That means you won’t need to water as often.
Final Thoughts
Knowing how often to water tomatoes is just one of the steps to having a great tomato harvest; it’s an essential part of your plants’ care. If you can get this right, you’re one step closer to have a huge tomato harvest this gardening season.
Written By
Bethany Hayes
Bethany is a suburban homesteader, growing over half of the vegetables, fruit, and herbs that her family of six needs each year. She raises chickens and homeschools her children. When she isn’t spending time tending to her garden, you can find her reading, crocheting, and canning.
I think it’s better to use straw and not hay when it comes to mulch. Hay decomposes faster and is better food for farm animals as it contains more available nutrients. Straw takes longer to decompose and contains materials better for your soil.
I think it’s better to use straw and not hay when it comes to mulch for many reasons.
Yes, but sometimes straw can be highly contaminated with weeds if it was grown in less than optimum conditions.
You’ve only talked about tomatoes planted outside. What about tomatoes grown in a hothouse?
I give my tomato.plants a deep water once a week. I might accelerate to once every five days if over 90. But they don’t need every day. That’s a lot of effort I can’t afford in a 3000 sf garden. The key is to make it a deep water to draw the roots down, and to mulch well with straw or salt marsh hay. My tomato plants routinely grow to six feet tall inside cylindrical cages I build.
hello!!
first i’d like to thank you for this great article! Very insightful.
i just have one question; does the 1-1.5 inches of water per week recommendation takes into consideration the evaporation rate? Surely it depends on the temperature and all, but I’m curious!
Thanks in advance!!
If you use much then yes.