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Growing Hydroponic Tomatoes – All You Need To Know

In today’s agricultural sector, we can see the evolution of plants that don’t need soil, direct sunlight, and water to grow. Now they only need a solvent with all the nutrients and artificial light.

In this article, we present to you the hydroponic ways to plant tomatoes in your kitchen garden or a grow tent.

Hydroponics – Short Introduction

Hydroponics is the method of growing vegetation without any soil or other necessities that plants usually require to grow. Instead, it uses a water-based solvent that contains a mixture of nutrients as well as minerals.

Some plants, such as terrestrial plants, grow in hydroponic cultures where only their roots submerged in the solvent. However, at times, there might be a need for gravel to support the roots in the mixture.

The nutrients which are usually used in such systems include fish excrements, fertilizers or manure of some domestic animals. These nutrients, together, help the plant grow as green as ever under no-soil circumstances.

Hydroponic vegetation offers many advantages. The most prevailing one is the decreased use of water.

Hydroponic can reduce the quantity of water you might be using at an exponential level. For example, if you are using 800 liters of water to grow 2 kilograms of tomatoes in a normal farming culture, you might need only 140 liters in hydroponic culture.

Hydroponic Tomatoes

Tomatoes require only a small area for growth since they are vining plants. Thus, they can easily be grown in a closed space as long as they can grow up and form many small intertwining vines.

Hydroponic tomatoes are planted in a solvent filled with nutrition with a non-soil material to support the roots. Growing these small red vegetables this way will not only let you spectate them but also ensure that they are embodiments of optimal nutrients. This will allow them to grow fast and healthier.

How to Grow Hydroponic Tomatoes?

Now that we have gotten the basic knowledge about hydroponics, let’s discuss how you can grow hydroponic tomatoes in your space. So without any further ado, let’s start!

Do you Want Seeds or Saplings?

You can grow tomatoes by either using their seeds or saplings.

We all know which seeds to use for vegetation. For a quick recap, the small, tiny yellow seeds that reside inside the red flesh of the tomatoes are used as seeds for growing them.

Saplings are small, tiny stems of the tomato plant. They are considered as the easiest way to grow hydroponic tomatoes in your own hydroponic grow system.

Though, if you are growing them outside, you might need to use seeds for effective cultivation. Most farmers and growers tend to grow tomatoes indoors since they are highly susceptible to different diseases and pests.

Moreover, growing them indoors and with seeds will let you grow various types of the vegetable, instead of the one, generic kind.

To grow seeds, you need to:

  1. Fill a tray with growing medium and place sprout tomato seeds in it.
  2. Wet the medium with water having a pH around 4.5.
  3. Keep your seeds in a damp and moist area at a temperature approximately between 20-25 degrees Celsius.
  4. The seeds will sprout in 10-14 days.
  5. Once, you see the tiny saplings, transfer them into your hydroponic culture immediately.
  6. Use sufficient intensity of light, whether it is natural or artificial.

Which Type of Tomato are you Growing?

Over the years, under the colonization of different emperors, it got sent to the rest of the world which increased its demand.

People from different parts of the world started cultivating them and now, around four centuries later, there are a variety of tomatoes that you can find all around the planet, each exotic and unique.

Some of the most prevalent types are as follows:

  • Red Beefsteak Tomatoes also are famous as the salsa tomato.
  • Heirloom Tomatoes.
  • Cocktail Tomatoes.
  • Green Beefsteak Tomatoes.
  • Roma Tomatoes.
  • Cherry Tomatoes.

Tomato Vines are of two distinct types. They’re either in the form of a bush which is popular as the determinate type or in the form of vines which are the indeterminate type.

While determinate varieties occupy more horizontal space, indeterminate ones occupy more of the vertical space.

The former growth rate can be limited while the latter has no fixed limit. They can grow, like their name suggests, indeterminately.

If you are growing tomatoes in an indoor grow tent, it is preferable to frow determinate varieties since their sizes can be restricted. Though, these types are generally difficult to prune. Whereas, pruning an indeterminate type is easy. All you need to do is select a single stem and let it grow while using a trellis as support.

In the end, it is important to note, that both types of varieties are a great source for capital accumulation in the market. So, it all comes down to the space you have and your preference.

What System Do You Want To Use?

There are some ways through which you can produce the desired outcome. Some of the most common ones are described below.

  1. Flood and Drain System: This system ‘floods’ the fruit with the solvent enriched with nutrients. After, the solvent drains as soon as it hits the mark of 2 inches from the top of the hydroponic system’s tank.
  2. Multi-Flow System: This system is an oversized version of the flood and drain system. Though it takes time to build, it is most economical when you have to grow a large amount of any sort of vegetation.
  3. Deep Water System: This system is small in size as compared to all the different types of systems. It is mostly used to grow cherry tomatoes.
  4. Nutrient Film Technique System: NFT System is mostly used by commercial producers. A pump is used to transfer the water to the tray in which you are growing the fruit. It further reutilizes the unused solvent effectively.

You do not have to run to a professional to get the system of your choice function. Most of the hydroponic stores sell kits that contain equipment as well as a manual to set up the hydroponic system.

If you are using a secondhand system, make sure you thoroughly clean every part of the system before building it up.

Where are you Going to Place your System?

Hydroponic Tomatoes - Do you want seeds or saplings

After selecting your system and the type of tomato you want to grow, select an appropriate place to set up your system. According to the opinion of experts, Hydroponics should be placed indoors or in a greenhouse.

These systems require a certain amount of control like you need to set the specific level of humidity as well as temperature to function optimally. Hence, you need to place your tank in a place where they are secluded from other rooms as well as outside.

Though you can easily grow hydroponics under direct sunlight, it is preferable if you grow them in a closed-off space so you can set its environment accordingly.

Set up your Hydroponic System:

The next step is to set up your hydroponic system. For that, just follow these simple steps:

1. Fill up a large container with water.

Use a tank that does not let any light in. This is important because it will prevent algae from growing inside your system.

Generally, a single tomato seedling requires 2.5 gallons of solvent so the larger your tank will be, the more efficient your hydroponic system will be. Try to buy a tank that can hold double the amount of water required.

You can use a plastic bucket or a dustbin for this purpose. If you opt to use a new bucket, make sure you clean the interior with soapy water to eliminate any chance of contamination.

2. Attach a tray above the tank.

A tray above your reservoir will help keep your hydroponics from flooding with water and nutrients. The tray will systematically allow the solvent to submerse it so that the roots can absorb it.

Take note that your tray should be well-built so that it can hold up your tomatoes. Moreover, you should place it above the tank so that excess solvent can easily drain.

You should buy a tray made from plastic so that there are no chances of corrosion that could later affect the plants and damage the tray itself.

3. Installation of a water pump inside the tank.

Water pumps are essential when it comes to setting up a hydroponic system. They made sure that you can easily pump the solution up to the tray and back. These are usually available in all home improvement retail stores.

Note the flow rate of the pump to better judge the kind and type of water pump you need for your system. Furthermore, there are water pumps that can easily adjust the flow rate according to your requirement so opt for adjustable ones.

4. Installation of tubes.

Since, water has to transport between the tray and the tank periodically, to ensure its safe transmission, buy PVC tubing or any type of tubing that befits the type of hydroponic system that you have.

Connect this tube between the tray and the water pump in such a way that the water conveniently circulates.

5. Installation of a timer.

Installing a timer to your water pump is a wise choice since it will let you control the flow of water between the tray and the tank according to your needs.

You can easily set the timer and then forget about it. Hence, you will have one less thing to worry about.

We recommend you to buy a heavy-duty timer with a waterproof cover. Most of the water pumps have an attached timer that comes with it, but if your pump does not have one, make sure to buy one that can easily be attached.

6. Test your Hydroponic System.

After the successful installation of all the equipment, make sure you test out your system at least once to see if it is operational or not. You need to check if the water can easily transmit to the tray and back. If not, check all the connections again.

Growing the Tomatoes

Now that we are familiar with the functionality of a hydroponic system, we will talk about how to plant the tomatoes in one.

1. Grow the seeds in a special culture.

You need to plant the tomato seeds in a tray with a special material rather than using regular soil. Soak the material you are choosing into water that has a pH of 4.5 before planting the seeds in it.

Plant the seeds just under the surface and keep any shielded surface over them to protect them against external factors like rapid transpiration.

Some of the growing materials include rock wool, perlite, and coconut coir.

  • Rock Wool: It is an excellent culture to grow tomatoes but make sure you are wearing gloves and a mask since it can irritate the skin.
  • Perlite: It is a cheap material that is highly effective when mixed with 5 percent vermiculite. Though, unfortunately, it quickly washed away in the flood and drain system.
  • Coconut Coir: When mixed with clay grow rocks, it becomes exceptionally practical for growing tomatoes.

2. Once the tomato sprouts appear, place them under artificial light.

As soon as you see tiny saplings of the fruit emerging from the special material, remove the shield you had placed over it and place them in a direct source of light.

All you need is a working grow light system that provides sufficient artificial light to your seedlings. Just be cautious of the intensity and the duration of light your saplings are getting. Too much sunlight to the roots can damage and burn them.

3. Transfer the saplings into the hydroponic system.

The moment you see small saplings protruding from the material in the tray, transfer them effectively into the hydroponic system so they can grow optimally.

Place each of the leave and roots at a distance of 10-15 inches from each other.

Make sure that the material used to plant them has a uniform distribution. However, if this seems difficult, you can opt for plastic pots that contain equal amounts of the growing material.

4. Set the timer for the circulation of water.

After you have successfully placed your vegetation in the hydroponic system, set the timer of the water pump accordingly.

Most experts suggest running the pump for a mere half an hour ever two and a half hours later. If they begin to wither, you need to increase the flow of water whereas if you see the roots getting soggy, decrease the rate immediately. Hypothetically, your culture should be damp all the time without any flooding.

As the saplings start to increase in size and you start seeing flowers and leaves sprouting you, change the water frequency accordingly.

5. Grow Lights.

You need to buy efficient, operational grow lights that provide just the right amount of sunlight to your plants. Ideally, growing tomatoes need around 16-18 hours of light a day.

For the remaining 8 hours, turn the lights off to let them rest before repeating the cycle.

6. Prune the plants.

We have already talked about the determinate and indeterminate plants above. Just be mindful of the plants that grow indefinitely and might need a bit pruning so they grow in the right direction.

7. Pollination

We are growing our tomatoes indoors but that does not exclude their need for pollination. So, without introducing insects to your grow tent, pollinate your tomato plants yourself. How? All you need to do is examine the petals of the plant.

As soon as they bend backward and expose the pistil and the stamen enriched with pollen are visible at the center of the flow, use a paintbrush to carefully transfer the pollen from the stamen to the pistil.

Repeat this process daily.

Maintenance of the growing Tomatoes

Hydroponic tomatoes growth process

Your job does not end here. There are a lot of factors you need to take into consideration while growing hydroponic tomatoes. Some of these are listed below:

1. Temperature.

One of the most crucial things to keep a check-off in a hydroponic system is its temperature. Daylight hours should have a temperature around 18 to 24 degrees Celsius whereas, at night, the temperature should be around 12.8 to 18.3 degrees.

To ensure that the cultivation has the optimal temperature, opt for fans and thermostats which actively regulated the temperature around the tent. Make sure, you keep a check of the existing temperature of the vegetation since it changes according to the life cycle of the fruit as well as the change in the climate.

The temperature of the environment is not your only concern. You should also notice the temperature of the nutritious solvent in which the roots of the tomatoes submerge. We recommend keeping their temperature between 68 till 72 Fahrenheit.

2. Installation of an exhaust fan.

You can install an exhaust fan so that the air inside the room can be circulated much more easily. The airflow created by the fan will also promote pollination.

3. Add the solvent to the tank.

You need to choose a solvent that is specifically available for hydroponics. Try avoiding organic solutions because they tend to decompose hydroponic vegetation and might create an unnecessary hassle for you.

So consult an expert before choosing a certain nutritive solution for your tomatoes.

4. Buy a pH kit.

A pH kit helps to detect the pH of the solvent you are using for your cultivation. Thus, it is a useful equipment to buy. This kit is cheap and available at all home improvement retail stores.

This kit will further let you judge if you need a more acidic solution or a basic one. Generally, Potassium Hydroxide raises the pH level whereas Phosphoric Acid decreases it.

5. Monitor the water regularly.

You need to keep in check the concentration of different nutrients in the water of the hydroponic system.

You can judge this better by an electrical conductivity meter which efficiently measures the concentration and lets you know whether you need to change the present solution or not.

6. Change the solvent as well as the water routinely.

If the plants in the tank do not look healthy, change the entire contents of the tank. Rinse the tank as well as the tray with water having a pH of 6.0 before setting up your system again.

Though, if you notice a decrease in the water level of the tank, do not add nutrient solvent in it, rather add water.


Hydroponic plants are grown by hobbyist gardeners as well as commercial businessmen. These plants have minimized the cost as well as the area required to grow plants. Moreover, these systems aid you to grow plants in a shorter time to their full potential.

We hope this article helped you gain insight into the hydroponic culture as well as how to grow hydroponic tomatoes. Happy gardening!