Your Introduction to Hydroponics

When most people think of gardening, soil comes to mind. But plants don’t actually require it to survive. They mostly need the nutrients and minerals in the soil. Plants can grow in water, gravel, perlite, rice hulls, pine bark, cedar shavings, and other mediums, or even suspended in air.
The science of soilless gardening is called hydroponics. It may sound like something devised in a modern laboratory, but it’s been around for thousands of years. The essential ingredient is an oxygenated mineral-nutrient solution that’s circulated through plants’ roots.

Some scholars theorize the ancient Hanging Gardens of Babylon, one of the Seven Wonders of the World, was a hydroponic system. The Aztecs grew maize, squash, beans, amaranth, tomatoes, chili peppers, and flowers in high-output chinampas, or floating gardens, which were hydroponic systems. A traditional hydroponics system is still in use on Myanmar’s Inle Lake, and similar systems probably existed in ancient India, Greece, China, and Egypt.

In the early 1600s, the British scientist Sir Francis Bacon, father of the scientific method, conducted formal research on hydroponics, which he called “water culture.” Laboratory experiments continued into the 20th century. In 1937, William F. Gericke applied the experiments to large-scale commercial applications, and the modern hydroponics movement was born.

Today many people identify hydroponics with marijuana growers, who’ve made use of the technology. But much of the world’s greenhouse produce is now grown in hydroponics systems, including some of the lettuce, tomatoes, herbs, and veggies in many supermarkets’ refrigerated cases.

Why Hydroponics?

Growing food without dirt, earthworms, and, sometimes, sunshine may go against common ideas of where healthy food comes from. But hydroponics has taken off for good reason. It offers a number of benefits over traditional soil methods and it may even help solve some of the world’s growing problems.

Water Conservation

Agriculture currently uses 80 percent of the fresh water consumed in the U.S. and 60 percent of it worldwide. Meanwhile a water scarcity crisis currently plagues every continent, particularly arid regions such as the American West.

With a name like hydroponics, it seems soilless systems would use a lot of water. However, on average, hydroponic systems use 10 times less water than soil agriculture because they recirculate fluids and cut waste. In the hope that soilless agriculture will help prevent worldwide water wars in the next century, the National Nuclear Security Agency built a hydroponics greenhouse in New Mexico’s Sandia Laboratory to test the feasibility of growing forage crops for livestock with hydroponics.

Land Conservation

Water is not the only resource in short supply. Many countries, including Great Britain, may face a significant shortage of farmland in the next two decades. Some studies estimate crop yield must double by 2050 to meet projected demands, and scientists warn that will not happen if current trends continue. In the past we’ve cleared forests and grasslands to plant crops, with grave environmental consequences. What if there’s a better way?

Some futurists, including microbiologist Dickson Despommier, are convinced hydroponics is the answer. In soilless systems, roots don’t need to stretch out as much because they’re supplied with all the nutrients they need. Crop yields are typically higher and more stable, and artificial lighting makes year-round crops possible. It currently takes a land area the size of Virginia to produce food for New York City. Despommier envisions cities feeding themselves with vertical skyscraper greenhouses. “If vertical farming in urban centers becomes the norm,” Despommier says, “then one anticipated long-term benefit would be the gradual repair of many of the world’s damaged ecosystems through the systematic abandonment of farmland.”

Less Pesticide Use and Runoff Pollution

Agriculture is the leading cause of water quality problems in the U.S., and pesticides, including endocrine-disrupting atrazine, currently contaminate our watersheds and drinking water. Many hydroponic farmers use zero herbicides or pesticides, and any system with the potential to curb pesticide use is important. Because plants experience less stress and are fed optimally, they’re healthy enough to resist any pests able to enter the greenhouse. Alternatively, organic methods can control pest infestations. Weeds are not an issue with hydroponics, since they need soil to grow.

Food Safety

We’ve all gotten used to headlines about deadly E.coli outbreaks. Twenty-three percent of foodborne illness deaths and 46 percent of foodborne illnesses are linked to eating produce, according to the Center for Disease and Prevention. Soil polluted by livestock waste is often pinpointed as the cause.

Because hydroponic systems are sterile and don’t have soil to be contaminated, disease outbreaks are less likely, especially in clean, well-run systems. (However, hydroponics does not completely eliminate the risk of foodborne illness. Proper precautions are warranted.)

Lower Food Miles

An eat-local movement has erupted across the country. Local produce is usually more nutritious, since vitamin content is depleted by light, temperature, and time. Moreover, local food doesn’t require the expense and energy expenditure of long-distance trucking. But how can people grow food in dense urban centers or inhospitable climates? Hydroponics may be the answer.

Take Emory University for example. The lettuce the school used to serve in their cafeteria had been trucked 3,000 miles before the students ate it. Students built a hydroponics system and now greens are grown 10 feet from the salad bar.

A number of companies, including New York-based BrightFarms, grow tomatoes, greens, and herbs hydroponically on the roofs of grocery stores. The supermarkets sign a contract to partner with BrightFarms for ten years, and in exchange, they’re able to sell the freshest, just-picked produce and eliminate some of their transportation costs.

Emory’s experiment and the growing number of partnerships between hydroponics companies and supermarkets indicate soilless agriculture may provide more local food choices in the future.

Potential Downsides of Hydroponics

Any time people change conventional ways, especially those as embedded in our identities as food cultivation, controversy is inevitable. Hydroponics is no exception, and it does have some potential drawbacks that should be weighed with the benefits. (However, it’s important to evaluate it in the context of the industrialized agricultural system we currently have, rather than an idealized one.)

Scientists are increasingly aware of the importance of the microbiomes in our soil. “There are millions of organisms in a couple cubic centimeters of soil,” explains biologist Jeanne Romero-Severson, and we’ve been unable to grow 90 percent of them in the laboratory. Because we still don’t fully understand the relationships between plants and soil microbes, it remains questionable whether we can reproduce them in a hydroponics system. For that and related reasons, a coalition of organic farmers oppose the USDA’s decision to allow hydroponically grown produce to be certified organic.

Most hydroponic growers claim their greenhouse-grown veggies are as nutritious as, or more nutritious than, conventional veggies, although data is hard to come by. There’s a widespread perception that hydroponic veggies are tasteless or watery, although the evidence is mostly anecdotal. In one blind taste test, hydroponically grown lettuce was rated as just as tasty as conventional or organic varieties. More nutritional analysis and taste testing on a variety of crops would be informative.

Several other issues may make hydroponics challenging or undesirable for some growers:

  • It can be expensive. Growers, especially large-scale ones, must make an initial investment to buy pumps, pipes, basins, lights, air filters, and fans.
  • Systems are made of fabricated materials, which require resources to build and maintain.
  • Commercial nutrient solutions are often mined and produced in factories and they can be pricey.
  • Systems, especially those with artificial lighting, can use a lot of electricity.
  • Large systems require technical knowledge and careful monitoring.

Many of those challenges can be mitigated for small-scale home gardeners. Setting up a soilless system can be inexpensive and easy and it’s an excellent way to understand the principles and potentials of hydroponics.

DIY Hydroponics for the Home Gardener

The first and often most daunting decision for any gardener is what to grow. The best veggies to grow in any garden are the ones a person or family enjoys the most. But some plants tend to work better than others in small hydro-systems.

Which Fruits and Veggies Grow Best

A small herb garden is a great way to get started. But before diving in, it helps to understand the basic parts and six different types of hydroponics systems.

The Basic Parts of a Hydroponics System

Six Different Types of Hydroponics

With a little basic understanding, anyone can make a simple system. A passive wick system is the easiest to start with because it doesn’t require a pump, timer, or electricity. (For those not DIY-inclined, many companies offer hydroponic starter kits.)

How to Make a Hydroponic Wick System in a Jar

Tools needed:

  • Wide-mouth quart-sized jar
  • Small planting container (with drain holes in the bottom) that nests in the mouth of the jar. (A small, plastic planter with the following dimensions fits perfectly: 3.5 inches wide at top, 3.25 inches long.)
  • A clean sock, towel, or t-shirt cut into 9-inch by 1-inch strips. (One strip is needed for each drain hole in the planter.)
  • Tape
  • Water soluble nutrients
  • Distilled water
  • Growing medium. (Coconut coir, perlite, and clay balls are good options for beginners. All of them can be sterilized and reused. Purchase online or at a hydroponics store.)
  • Small herb transplant

System setup:

  1. Sterilize the jar and planting container by washing in soap, water, and diluted vinegar. Rinse well and dry.
  2. Using the distilled water, follow the directions on the nutrients to make some nutrient solution.
  3. Soak the strips of towel, T-shirt, or sock in the solution.
  4. Thread one strip of the soaked material through each drain hole. Temporarily tape them to the top of the planting container.
  5. Braid the strips hanging out the bottom of the container together so there’s one wick hanging down.
  6. Fill the planter midway with growing medium.
  7. Gently rinse the soil off the plant roots and transplant it into the growing medium, adding enough medium around the roots for support.
  8. Remove the tape that held the cloth strips to the top of the planter. Space them evenly around the plant roots. They will deliver the nutrient solution to the roots.
  9. Fill the jar halfway with nutrient solution.
  10. Nest the planter in the jar. The solution should be one to two inches beneath the level of the planter and the wick should hang into the solution.
  11. Put the system in a sunny window or under a grow light.
  12. Monitor, and add nutrient solution as needed.
  13. Every two weeks wash the jar and replace the nutrient solution. (Reuse old solution to water houseplants.)
  14. Enjoy fresh-grown herbs.

Hydroponics systems are already making food easier to grow in deserts and in land-starved countries like Japan where there are concerns about radiation-contaminated soil. If some futurists are correct, hydroponics could help solve impending food, water, and environmental crises. At the very least, soilless systems offer urban apartment dwellers and people living in inhospitable climates the ability to grow food, and that’s no small feat.

Don’t forget to check-out this handy IndoorGardeningChecklist – print yourself a copy!


Setup your own hydroMazing

Setup and Use hydroMazing

  • The Controller ( Arduino Nano Expansion Board with nRF24L01 and DHT sensor ) uses 433MHz Transmitter to send codes to remote-controlled AC Outlets or can connect directly via a transistor, MOSFET, or relay.


  • Raspberry Pi Web Services Module ( with nRF24L01 ).


  • Optional The Advanced Controller ( Arduino Nano Expansion Board with nRF24L01 and uses 433MHz Transmitter to send codes to remote-controlled AC Outlets or can connect directly via a transistor, MOSFET, or relay.  Supports additional sensors:  E.C., pH, Light Intensity, more floats and flow-rate sensors.


  • Optional Web-Camera using Raspberry Pi ( with USB Web-Camera ).


  • Optional Zone/Node Controller(s) ( Arduino Pro-Mini with nRF24L01 connects directly via a transistor, MOSFET, or relay.  These units are solar-powered with a battery backup.  Also, supports additional soil-moisture sensors.


  • Optional The Monitor (Arduino Nano Expansion Board with nRF24L01 ) connected to an Arduino Uno with LCD w/ Buttons Shield.

Each module requires a standard 5 volts power source such as USB.

Setup hydroMazing

Plug-in appliances to their corresponding remote controlled AC switch units:

  1. Intake Ventilation Fan
  2. Exhaust Ventilation Fan
  3. Humidifier / Other
  4. Heater / Additional Lighting
  5. Pump(s)
  • Install the hydroMazing Controller Unit inside the growing area.
  • Provide power to the controller and monitoring devices.

hydroMazing’s default sensors:

  • DHT ( Temperature and Humidity ) Sensor
  • Dallas Temperature Probe Water Temperature Sensor
  • Flow Rate Sensor
  • Float Switch – Low water level
  • Float Switch – High water level

The hydroMazing controller is designed to operate ventilation fans for air circulation, water pumps, occasionally a humidifier, heaters, or any other appliance that is necessary to maintain an ideal environment for plants to grow.  Monitoring and controlling the system is mostly done for us, but when the hydroMazing needs to alert us to a problem it can by using the Raspberry Pi.

Using float switches:

  1. Top float switch used to indicate vessel is full of liquid.
  2. Middle float switch provides warning or triggers a pump to refill.
  3. Bottom float switch turns off pumps and notifies attendant that vessel is out of liquid.

Using the flow sensor’s data we can determine the flow rate of the liquid being pumped.

Hook Up Your Raspberry Pi

Connecting all your devices to the Raspberry Pi is very easy, but you want to do it in a specific order so it can recognize all your devices when it boots up. First, connect your HDMI cable to your Raspberry Pi and your monitor, then connect your USB devices. If you’re using an ethernet cable to connect to your router, go ahead and connect that as well.  Finally, once everything is connected, go ahead and plug in your power adapter. The Raspberry Pi does not have a power switch, so once you connect the power adapter, it’ll turn on all by itself.

Connect to Your Wi-Fi Network

Connecting to your Wi-Fi network works the same in Raspbian as it does it any modern operating system.

  • Click the network icon (it’s the one with two computers) in the top right corner.
  • Select your Wi-Fi network name, and enter your password.

That’s it, you’re now connected to Wi-Fi. This will work in both the command line and in the graphical interface, so you only need to set it once. If you have an older Pi and you’re using a Wi-Fi adapter like this, the process is the same.

You have several devices connected to your WiFi router, so how can you tell the outside where you are serving-up Raspberry Pi?

Getting Online

The following section assumes you have an updated and upgraded Raspberry Pi 3 or equivalent, and installed L.A.M.P. (Linux.Apache.MySQL.PHP.)  Excellent article for getting started and’s installing LAMP.

You have several devices connected to your WiFi router, so how can you tell the outside where you are serving-up Raspberry Pi?  Let’s get familiar with our router’s advanced settings in your router manufacturer’s configuration tool.  Most home networks use one of these common IP addresses for their gateway to the Internet:


You will need to login to your router’s configuration tool.  The username and password should have been assigned at the time of setup.  First, we need to reserve an IP address for our Raspberry Pi to use on a regular basis.  Typically, the router will have a DHCP (Dynamic Host Configuration Protocol) Settings section, List and Bindings, etc.  The Raspberry Pi and all other devices on your LAN should be listed here.  Hopefully, your router will have a somewhat intuitive interface that will make sense as to how to assign an IP address to a device or MAC address.  If all else fails, consult your manufacturer’s instructions.


The default port for web requests is 80.  You can leave the default unless your Internet Service Provider doesn’t allow port 80.  Next step in your router’s configuration is to have the router forward all incoming requests on port 80 to the Raspberry Pi.  Typically referred to as, Port Forwarding or Port Range Forwarding.  You will want to associate the Raspberry Pi’s IP address so that it will receive all incoming requests on port 80 or whatever port you find most appropriate.  (The most secure web server is one that is not connected to the Internet 😉  The default port for SSL is port 443.  Next step in your router’s configuration is to have the router forward all incoming requests on port 443 to the Raspberry Pi.  Motion Web-Cam Streaming:  The default port for motion is port 8081.  Next step in your router’s configuration is to have the router forward all incoming requests on port 8081 to the Raspberry Pi.

You could also allow Telnet, FTP, SSH, VNC, etc but I do not recommend unless you are familiar with the security risks associated with such services.

Get Yourself A Domain Name

Check for the DDNS ( Dynamic Domain Name Service ) Setting in your Router’s advanced configuration settings.  Most routers will support one or more of the following, http://www.dyn.com, many others search Google for “Dynamic DNS”.  The service will offer the ability to register a domain name to associate with the Dynamic IP address that is assigned to you by your Internet Service Provider.  Typically, your router or a software plugin that you download and install will update the Dynamic DNS service’s database when your assigned IP address changes.

Secure Socket Layer

Let’s Encrypt our connection with the Raspberry Pi.


Rather than apt-get Cerbot, I download the latest version directly from its repo:

sudo git clone /etc/letsencrypt

Easy SSL through Automation

Certbot has a fairly solid beta-quality Apache plugin, which is supported on many platforms, and automates both obtaining and installing certs:

sudo /etc/letsencrypt/certbot-auto


Your domain name for your hydroMazing should now be secure.

Is Hydroponics a Scam?

What do you think when you hear the term “hydroponics”?

Do you imagine technicians in white lab coats tending sterile trays on a space station?

Or maybe you think of massive commercial operations that cost more thmuch-budding-in-tent-sman you make in a year?


Or maybe you think of a group of stoner’s growing weed?


Two of the biggest reasons that hydroponics has such a bad reputation, is that purists swear it is unnatural to garden in a medium other than soil, and hydroponics stores are often motivated by selling you the most expensive equipment and consumables.


The truth about hydroponics, as with most things in life, is somewhere in the middle. If you are ultimately interested in gardening using aquaponics, consider hydroponics the gateway to aquaponics.

History of Hydroponics

The earliest examples of hydroponics date back to the Hanging Gardens of Babylon and the Floating Gardens of China. Humans used these techniques thousands of years ago. Although the general theory behind hydroponics remains the same, modern technology has enabled us to grow plants faster, stronger, and healthier.

The best way to find out, is to try it for yourself.

I enjoy helping people, like myself, who prefer to garden outside but want to be able to extend or even grow all year long.  Think of indoor gardening in the same way that you think of brewing beer at home.  Indoor gardening is a hobby for most people do not have access to large indoor spaces, so it is unlikely that they would be able to grow enough plants to make a profit.  The greatest benefit to growing your own consumables is that you will appreciate the amazing results even more because you’ll know how the plants were treated.

Where Do I Start?