Hydroponic Tomatoes

Today you’re going to see exactly how to grow hydroponic tomatoes year-round, and understand which varieties are best suited to hydroponics. We’re even going to recommend the best system setup to optimise your system for the best yields! Let’s get started.

How To Grow Hydroponic Tomatoes

Tomatoes are one of the best crops to grow in a hydroponics system. They’re hardy and respond extremely well to being grown indoors.

You might have read that tomatoes are challenging to grow, and while they’re certainly more complicated than, say, lettuce – they aren’t as tricky as you might have been led to believe.

As long as you choose the best hydroponics nutrients, the proper lighting and tend to your plants, then you’re almost guaranteed to be enjoying the fruits of your labour in a couple of months.

Selecting Tomato Varieties

Choose tomato varieties that are well-suited for hydroponic cultivation. Look for compact and determinate varieties that thrive in controlled environments. Varieties such as ‘Celebrity,’ ‘Roma,’ and ‘Beefsteak’ are popular choices for hydroponic tomato production.

Setting Up the Hydroponic System

Select a suitable hydroponic system for growing tomatoes. Options include nutrient film technique (NFT), deep water culture (DWC), or drip irrigation systems. Set up the system according to the manufacturer’s instructions, ensuring proper water circulation, aeration, and nutrient delivery.

Seeds Vs. Saplings

So before we get deep into the how, first we should take the time to understand which is the best way to start – either with tomato seeds or sapling plants.

While saplings are the easiest route to get started they do come with some issues.

Plants grown outside can be contaminated by pests and bacteria which could potentially ruin a crop. That’s why most veteran growers will grow their seedlings indoors.

Getting Started

To grow seedlings indoors, start by placing seeds in a tray filled with a growing medium, wet the medium with water (a pH of 4.5 works best), then keep the seeds covered in a moist, damp area with a temperature of 20-25 degrees Celsius / 67 to 77 degrees Fahrenheit.As soon as you see the seeds sprout you should transfer them into your hydroponics system ensuring there’s adequate light.

The Right Lighting

If there’s one thing that tomatoes love it’s light.In fact, they’ll need around 8-10 hours of light per day with some varieties needing upto 18 hours! Once the plants mature they’ll then need around 8 hours of darkness per day to allow for respiration.When it comes to lighting, your best choice is to use metal halides, however, you’ll still be able to get good results using CFLs and LEDs.

Temperature Range

While tomatoes can tolerate temperatures from 13 degrees Centigrade / 55 degrees Fahrenheit the sweet spot usually is 20-25 degrees Celsius / 67 to 77 degrees Fahrenheit during the day and 13-18 degrees Centigrade / 55-64 degrees Fahrenheit at night.

Anything lower than this and you risk killing the plants, which are why a grow tent can be a useful tool to maintain temperatures.

Hydroponic Nutrients for Tomatoes

In order to grow well, tomatoes require a lot of nutrients, and if you’re looking for a bumper crop, you’ll want to look for a plant nutrient mixed designed for tomatoes.

These specialist tomato hydroponic mixes are higher in phosphorus, nitrogen and potassium which are the nutrients the plants crave!

pH & EC Requirements

Tomatoes like a slightly acidic pH of between 5.8 to 6.3 and EC levels of between 2.0-3.5 milliMhos.While a pH meter can be handy, there are certain things to look out for that will provide a quick check on how your plants are doing:

  • High pH or low nutrient quality will result in the plants having yellow leaves
  • Red stems and curled-up leaf tips are a sign of low pH levels
  • Flowers falling off early are a sign of potassium deficiency

Grow Media

With the right growing medium, you can almost guarantee a high yield. Tomatoes, unlike many other crops, actually do well in several different grow mediums.

Here are a few of our favourites below:

  • Clay pellets
  • Rockwool
  • Perlite
  • Coconut coir

Systems For Tomatoes

While tomatoes are hardy enough to grow in a wide range of hydroponic systems, due to the high amounts of nutrients needed, some hydroponic systems aren’t as suitable.

A good example of this is that while a recirculating system will work in the early days of your plant’s live, once they start flowering, pH management can be a nightmare.

You should consider the following:

  • Nutrient Film Technique
  • Deep Flow Technique
  • Drip System
  • Ebb-and-flow

Best Tomato Varieties for Hydroponics

With thousands of tomato varieties available, how do you pick the right one for your hydroponics setup?

Determinate Vs. Indeterminate

There are two types of tomato – determinate or indeterminate so which is correct?

Indeterminate tomato plants will grow up on a vine and with pruning and support will repeatedly grow and bear fruit.

Determinate plants, on the other hand, will spread out horizontally along the ground and only grow vertically up to four feet. Determinate plants are the most popular among hydroponic gardeners.

Our Top ChoicesHere is some of our favourite hydroponic tomato varieties:

  • Brandywine,
  • Giant Beefsteak,
  • Cherry,
  • Plum,

Pruning and Training

As the tomato plants grow, it is essential to prune and train them to optimize their growth and productivity. Remove any suckers that develop in the leaf axils, and provide support for the main stem using trellises or stakes. Regularly monitor the plants and adjust their growth to maintain an open and well-ventilated canopy.


Tomato plants require proper pollination to produce fruit. In indoor hydroponic systems, natural pollinators may not be present. You can manually pollinate the tomato flowers by gently shaking or tapping the flower clusters to release the pollen. Alternatively, you can use an electric toothbrush or a small brush to transfer pollen between flowers.

Watering and Maintenance

Monitor the water level in your hydroponic system and ensure the plants receive sufficient moisture. Avoid overwatering, as it can lead to root rot. Regularly check for signs of pests or diseases, and promptly address any issues that arise. Prune the tomato plants as needed to maintain a healthy and productive plant structure.

11. Harvesting

Tomatoes are ready to be harvested when they reach their full color and have a firm texture. Gently pick the ripe tomatoes, being careful not to damage the plants or other developing fruits. Hydroponically grown tomatoes often have exceptional taste and quality, offering a rewarding harvest.

The Bottom Line

Growing hydroponic tomatoes can be great fun. Those looking beginners looking to step up from leafy greens will enjoy the extra challenge of nutrient management and seeing your plants flower and fruit.

Similar Posts