Grow Plants Without Soil

How to Grow an Indoor Garden Without Soil

Do you want to eat more fresh vegetables, save money on produce, and help the environment all at the same time?

Of course, you do! Everybody would if they could.

Well check this out: you can grow vegetables indoors without having to bring any dirt, bugs, or germs into your home. Just picture it, you’re making a salad for dinner and you grab fresh lettuce, cucumbers, and carrots from your own indoor garden.

That sounds pretty good does it not? You bet it does!

Now the only question is the “how” of growing vegetables – and maybe even fruits – indoors without using soil. Believe it or not, it isn’t that difficult to do, and It’s quickly becoming very popular.

So, how do you start your own little – or not so little – indoor garden?

I’m so glad you asked!

How to Grow an Indoor Garden Without Soil

How can plants grow without soil?

It seems unnatural, I know, however, growing vegetables, fruits, and herbs without using any dirt is not only natural it is considered by many to be the best way to grow. The fact is, plants only need five things to thrive:

  • Food
  • Light
  • Air (oxygen)
  • Water
  • Support

According to Frank McDonough, the Los Angeles County Arboretum and Botanical Gardens’ plant information consultant,

As long as the plants have nutrients, they can grow and can even be healthier plants.”

So, how exactly do you grow plants that have the five things they need without using soil for the support and food part of the equation? Good question. I have a good answer, Hydroponics.

What’s Hydroponics?

This is the technique of growing plants without soil by soaking their roots in nutrient rich water. It allows more food to be grown in less space and in places where it otherwise couldn’t be grown.

Sources cannot reach a consensus as to who should get credit for first inventing hydroponics. The term itself was undoubtedly coined by a California scientist in 1936 after he grew a tomato plant in a tub that grew to be a whopping 25 feet tall.

When done right, hydroponics can produce food that’s free from bacteria, viruses, soil-born pests, and weeds. This results in healthier food and better yields for your efforts.

Furthermore, by carefully controlling the nutrient intake of your plants you can get food that’s full of the things your body needs. “Farmers” can even engineer plants to contain specific levels of specific nutrients for specific dietary needs. For example, lettuce with low levels of potassium for those with kidney disease.

Hydroponics takes many forms. Below are a couple of those hydroponic techniques.


Hydroponics vs Aeroponics

The process of Aeroponics uses an air chamber where plants (such as these) grow using a system that sprays the roots of the plants with a light nutrient-rich mist and was developed by Dr. Franco Massantini, professor of Ecology, at the University of Pisa in Italy in the 1970s.

This is one of the more expensive options for indoor gardening. In fact, the Tennessee based company Juice Plus sells an Aeroponic Tower Garden that’s 5 feet tall and can accommodate up to 20 plants for somewhere in the region of $500.

It’s an excellent alternative to traditional farming and is on par with organic farming. Moreover, a University of Mississippi study found that the yield of Aeroponic farming is 30 percent more than other forms with nutritional values that were comparable to organic and superior to traditional.

Film Farming

This may well be the next step in commercial farming.

Yuichi Mori, a chemical physicist, founded Mebiol Research and Development Center roughly one hour outside of Tokyo, Japan. While there, he and several colleagues experimented for a decade to develop the concept of film farming.

Film farming is a soil-free farming system that employs a thin, transparent polymer film made of a super absorbent material, hydrogel.

This system develops seedlings on top of the film. Thus, the plant grows on top of the polymer film and the roots spread across the under-surface of the membrane in wispy formations.

The process of film farming works by allowing the plant to soak up nutrient-rich water absorbed by the polymer membrane through its microscopic pores. These pores also block bacteria and viruses.

By forcing the plants to work harder to absorb the nutrients and water, it puts the plants under stress. This stress causes the plants to have higher levels of phytochemicals, amino acids, and sugars. This can result in the foods produced this way being more nutritious and better tasting.

Other benefits of film farming include the fact that it uses 90 percent less water than traditional or organic farming. Also, you can use this type of farming nearly anywhere, such as:

  • In the desert
  • On a rooftop in New York City
  • Alaska in the winter
  • Even on contaminated soil

Companies Pulling the Hydroponics Bandwagon

Hydroponic System

Hydroponics has already spread across the world with different plants being popular in different areas. These include:

  • A variety of herbs, lettuce, and tomatoes in Ontario, Canada.
  • Cucumbers and tomatoes are hot in the United States.
  • Australia loves hydroponic strawberries.

As it grows in popularity among the ecological, agricultural, and commercial communities, some well known companies have put the innovation to beneficial use. They are leading the charge in making hydroponics the way to farm.

National Aeronautics and Space Administration (NASA)

Nasa – yes, that NASA – has used hydroponics for years to provide fresh food to their astronauts. They also have scientists in Antarctica that are testing hydroponics techniques for use on missions to Mars – yes, that Mars.


The “Happiest Place on Earth” uses hydroponics in its EPCOT (Experimental Prototype Community of Tomorrow) attraction. Fresh cucumbers, lettuce, and tomatoes grow in hydroponic gardens to service the customers in their varied eateries.


This giant of the electronics industry known for its computer product offerings has converted a factory that they formerly used to manufacture semiconductors for fabricating computer microchips. It now houses a tightly sealed indoor cultivation area.

Manned by engineers in white cleanroom suits, their plantation uses a cloud-based program to keep an eye on the many sensors that track plant growth.

With this system of monitors, the engineers can adjust the levels of light and nutrients the plants get to produce the desired results in growth and development.

Little Fish

Other lesser known companies are making hydroponic waves as well, for example:

  • AeroFarms in New Jersey has become the world’s largest vertical farm with the ability to reap in the region of one thousand tons of greens per year.
  • Spread – Japan’s largest vertical farm company – produces more than 20,000 heads of lettuce each day.

So, how does this apply to you?

Hydroponic GardenWow! You’re just full of good questions. It just so happens that I have an answer for this question too. Growing plants hydroponically does not require a factory sized space, a degree in botany or engineering, or anything else that you cannot easily obtain.

Frank McDonough – the plant information consultant from LA mentioned earlier – seems to agree. He said,

“Hydroponics uses easily accessible materials: plastic tubs, net pots, aquarium stones, and air pumps.”

You can buy complete hydroponics systems online for several hundred dollars. Conversely, you can build a hydroponics system at home with just few items.

Build Your Own Hydroponic Garden

Rising produce prices, mistrust of commercially produced food, and dwindling space all propel hydroponics into the minds of regular people like us.

Thanks in part to the pioneering efforts of the people and companies named above, there are now a plethora of hydroponic systems available for purchase online. They are expensive but simple to use and quick to set up.

They are also completely unnecessary.

Anyone can build a hydroponic nursery on their own, although it may be more fun to include your family. It seems like everyone has a “best ever” program for growing food hydroponically.

Regardless of which of these you follow, there are some basic steps and tools that are simple to obtain and follow.

Even if you aren’t mechanically inclined and you’ve never put together more than a sandwich, you can create your own indoor hydroponic garden.

What You’ll Need

  • 11 seedlings of the veggies, fruits, or herbs you want to grow.
  • A black Rubbermaid storage container with a lid, 18 gallons, to use for a water reservoir. It has to be black to prevent algae growth in the water. Otherwise you’ll need…
  • A can of black spray paint.
  • An aquarium air pump, like this one on Amazon, to aerate the water properly.
  • An airstone for some major aeration of the water. They are a commonly used tool in hydroponic systems that creates provides the root zones of the plants with oxygen. It’s traditionally a chunk of porous stone or limewood attached to an air pump by a small tube. The size of the airstone determines the size of the bubbles and thus, the amount of oxygen released into the water.
  • Some 3-inch Net pots to hold your plants as they grow. They anchor the plants in the system.
  • A medium such as aquarium stones, gravel, rockwool, “coir” (coconut fibers), clay balls, organic cotton batting, etc. Various plants thrive in distinct categories of growing media.
  • Tubing … lots of tubing. The specific system described here requires 25 feet of tubing, but you should get more than that for unforeseen needs.
  • A drill with a 3-inch bit – or something else you can use to bore/cut holes in the lid of your storage container.
  • A pH level tester kit.
  • Some kind of nutrient solution to feed your plants. You can buy nutrient solutions online or at local greenhouses/nurseries.

Starting the Seeds

Seed Growth

This is where it all begins. After all, you cannot have a plant without a seed.

Make sure that you use more seeds than you need for your garden. Some of the seeds won’t germinate and others will fall victim to disease.

By planting extra, you ensure that you’ve a selection of seedlings that you can choose the most promising of to put in your hydroponic garden.

Then let the germination begin!

  1. Start the seeds in starter pods of an inert growing medium. There are many starter pods to choose from commercially or you can use perlite, rockwool, or another great seed incubating medium.
  2. Place these cubes in a small container filled with one inch of water to keep the seeds moist and encourage them to sprout.
  3. Watch for seedlings to reach two to three inches so that you know it’s time to transplant them into your hydroponic garden.

Meanwhile Back at Headquarters…

While you’re waiting for your seeds to become seedlings ready for transplant, you should be building the hydroponic garden structure into which you’ll be transplanting them.

The seeds should take roughly a week to two weeks, so you’ve plenty of time.

  1. Place net pots upside down on lids of storage containers and trace around them.
  2. Use the drill and circular bit – or scissors, or a saw, or whatever — to cut out the circles on the lid of the tub. The net pots will sit inside these circles so make sure when you cut them out you cut a little inside the line rather than outside. You can then use a file to smooth out the rough insides of the circles.
  3. Then you need to thoroughly paint the outside of your container with black spray paint. Apply several coats – allowing 10 minutes or so for it to dry – to ensure that it covers the entire thing, don’t miss a single spot. Even when you’re growing indoors, blocking sunlight is important. Sunlight will encourage algae growth in the nutrient solution which can inhibit root growth and clog the system. Wash thoroughly afterwards.

Now that you’ve effectively modified your Rubbermaid container to be a hydroponic reservoir you need to choose a place for it in your home. The ideal place is somewhere that gets a lot of natural sunlight, has access to electrical outlets, is out of the way, is easily accessible, and level.

There may be no place like this in your home but that doesn’t mean that you cannot have an indoor garden. It simply means that you’ll need to provide grow lights for your plants, since that’s the one requirement that you can change.

So, pick a place that’s out of the way but easily accessible, is level, and has ready accesses to electrical outlets… then get yourself a decent light for growing your garden.

  1. Now you need to fill your tub until the water submerges the bottom quarter inch of your net pot, about four-fifths of the way full (should be just below the handles). Since you found a level place for your indoor garden, you know all of the net pots will get the same amount of water.
  2. Drill a small hole through the top to thread the air tubing through and connect it to the air stone. Smaller air stones may require something to weight them down. You can zip tie them to something heavy like a clean masonry brick to keep them on the bottom. Place it in the center of your tub.

It’s a smart idea to plug in the pump at this point and make sure it makes the airy bubbles that indicate proper aeration of the water. There’s no point moving on to the next step if your pump isn’t sufficient.

Now It’s time to attach the air pump to the tub. Simply screw it to the tub as high as possible. Keep in mind that too low will create water leakage and too high may interfere with the lid.

Dump out the water until your seedlings are large enough for transplanting. When they are, refill as before and add the nutrient solution according to the label of the kind you purchased.

Afterwards, allow the water a half an hour then test the water’s pH balance and adjust it until it’s right for your garden.

Transplanting your Seedlings

Now that you’ve a fully functioning hydroponic system and seedlings you’re ready to go. This is the point where you’ll “plant” your seedlings into the net pots.

  • Cover the bottom of the net pot with your growing medium.
  • Place the seedling in its starter pod centered on top of it.
  • Attempt to thread the roots straight out the bottom of the net pot.
  • Fill around the seedling with the growing medium so that the plant is stable in the net pot.
  • Place the net pots in their spots on your hydroponic reservoir/tub.

Now turn on your growing light – if you used one – and watch your garden grow!

Well, actually you’ll need to carefully monitor the pH level of your reservoir to ensure that it remains optimal and add more of your nutrient mix according to the directions on the label. I recommend that you test the pH at the same time.

Just remember to allow the water a half an hour after adding the nutrient solution before testing. Make the necessary adjustments as you did before.

Wrapping It Up

So, now you have your very own indoor hydroponic garden. Most of these types of gardens grow veggies, flowers, or herbs. However, there’s no rule saying that’s what you have to grow … grow whatever you want.

Change it up. Experiment.

It’s your garden; the only real requirement is that you enjoy it!

How to Grow an Indoor Garden Without Soil was last modified: November 21st, 2019 by The Practical Planter


    1. Hi, Cheryl!

      The most accessible way to acquire seedlings is to grow them yourself from any traditional gardening seeds that you can purchase locally or online. However, if you would prefer to buy seedlings that are ready to add to your hydroponic system right away, you can buy traditional seedlings at your local garden center. I would suggest that you spray them with insecticidal soap in case they are carrying any pests, then rinse away as much of the soil from the roots as you can. Please be aware that not all plants will do well with having their roots rinsed and results may vary. Good luck!

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