Chris Telden is an avid gardener of edibles. A former city dweller, she's always learning of ways to reconnect with the earth.
Whether you plan to build your own hydroponics system or buy one pre-built, with this guide, you can learn the basics: what hydroponics is and how it works, a bit about its history, and pros and cons to help you decide for yourself if it's worth your time. Discover the advantages to growing hydroponic plants and the essential points you must know before you begin. Find help within for deciding what to grow and the best way to maintain your garden.
History of Hydroponics
A quick look at the history of hydroponic gardens shows that hydroponics is not a modern invention.
Believe it or not, the origin of hydroponics lies with the Babylonians and Aztecs, who had their own versions of hydroponics. Since the 17th century, people have been performing research into the makeup of plants by growing plants in water.
Modern hydroponics as we know it, however, began in the first half of the 20th century with research done at the University of California, Berkeley.
Definition of Hydroponics
If you are growing a hydroponic garden, this means you are growing plants not in soil, but in water that has been:
- enriched with mineral nutrients and...
- added to a bulky medium, such as rock wool or vermiculite...
- in an enclosed container.
Now the origin of the word "hydroponic" becomes clear. In Greek, "hydro," meaning water, refers to the fluid in which the plants are grown. "Ponos," meaning labor, refers to the fact that the hydroponic cultivation system replaces the physical work of pollination, nutrient absorption, and hydration that goes into plant growth in nature.
Too Good to Be True?
Hydroponically grown plants are sometimes suspected of containing toxic chemicals because they grow so heartily. The assumption is that toxic chemicals or hormones have been used to boost their growth. Actually, it is the higher availability of nutrients and the optimal conditions for growth that are responsible for the robustness of hydroponic plants.
Hydroponic gardening is not synonymous with organic gardening, though there are similarities. In organic gardening, attention is paid to the purity of the soil; in hydroponic systems, attention is paid to the purity of the bulky medium and enriched water.
How Can Plants Grow Without Soil?
To grow, plants need to absorb water, air and minerals through their roots, which they do by the process of osmosis.
They also need to absorb light and air through their leaves. They then use this light and air to convert the water and minerals they've absorbed into plant tissue. This process is known as photosynthesis.
Plants actually get all they need to survive, and then some, through hydroponic gardening systems. Hydroponic units are designed to give plants access to all the light, minerals, moisture, and space they need to thrive.
Plant Health: Hydroponic vs. Soil-Grown
Generally, hydroponic plants are healthier than those grown in soil. Think about human beings. If you had all of your needs met - if all the food, shelter, social interactions, activity, space, and comforts you needed were readily available - you would probably be healthier than would someone who lacks these things. And if most of your enemies were kept at bay, your risk of harm would be low.
Plants, too, thrive in a situation where they get all of their needs met. When the conditions are optimal and they get sufficient nutrients, plants grow well. Plants have limited growth when they lack important nutrients or when the nutrients are not in the right balance. And hydroponically grown plants grow better away from most pests such as insects, worms, and fungi.
Pros and Cons
Consider the advantages and disadvantages both of hydroponics as a total working system and of the advantages over soil - that is, is hydroponics better than soil?
The disadvantages of hydroponics boil down to:
- Expense - hydroponics can cost a pretty penny, especially in the beginning
- Energy and resource usage - the hydroponic gardener relies on equipment and electricity rather than letting nature do most of the work.
- Knowledge level - You do need to do your research and know what you're doing to build a successful hydroponics garden.
- Diligence - Plants react extremely quickly to nutritional fluctuations. You'll need to stay on top of monitoring your garden.
The advantages of hydroponics gardening are:
- Growing plants in water saves your back. You do not need to prepare any soil or remove any weeds. Physically, hydroponic gardening is much easier on your joints than soil-based gardening.
- Hydroponic gardening uses fewer pesticides and is less toxic.
- Hydroponic gardening requires less space.
- Gardens grown in water can be portable, moving indoors or outdoors, as the weather permits.
- With a hydroponic garden, you can enjoy year-round production.
- Plants in a hydroponic garden have no competition for nutrients. Like a domestic cat that's fed all the food it wants, the roots of hydroponically grown plants feast on a wealth of nutrients balanced just for them.
- Hydroponically grown plants grow faster than soil-grown plants.
- Hydroponically grown plants have a greater yield than soil-grown plants.
- You enjoy a greater selection of plants to grow in your hydroponic garden than you would if you were growing plants in soil. With a hydroponic garden, you can grow almost anything - from basil to horseradish, from roses to orchids, from potatoes to coconuts.
- Hydroponic gardening is earth-friendly, using less water than soil-based gardening.
As you can see from the lists above, the advantages seem to far outweigh the disadvantages of hydroponic gardening.
Checklist: Before You Start
Before you run off and stock up on hydroponic supplies and kits, educate yourself about growing in hydroponic systems by reading or taking classes or talking to other hydroponic gardeners. Experimentation is at the root of hydroponic gardening, and that's half the fun. But you can avoid repeating common mistakes by becoming familiar with certain subjects.
For example, indoor growing will rapidly teach you that certain factors you took for granted in growing your soil-based gardens you must now regulate and control. Teach yourself about these factors, which include:
- Water conditions such as acidity, temperature, and oxygen content
- Air characteristics - that is, humidity, temperature, and light sources
- Air quality - that is, pollution and ventilation. Hydroponics air filters and air pumps are designed to control the pollution and provide ventillation.
- Mineral nutrients for hydroponic plants to replace those that would exist in the soil
- Growing medium for hydroponics, replacing the "bulk" of soil, which provides a structure in which the plants grow and provides moisture and air circulation
- Seeds, pollination and plant cloning - yes, unfortunately, no bees, birds, or breezes are available indoors to spread your seeds
You'll be glad of this background information when you begin getting your hydroponic supply kit together and actually start to garden!
Decisions, Decisions, Decisions...
- Decide whether you intend to grow outdoors or indoors exclusively, or a combo. If you're going to be moving your unit outside, it must be a portable one.
- Decide whether you want to buy a system that's already been manufactured or build your own. Keep in mind that a purchased garden is a great time-saver and allows you to be away from your hydroponic garden for longer periods of time. It also tends to allow for more accurate nutrient provisioning and better drainage. Still, if you build your own homegrown system, you can design it precisely to the conditions you specify.
- Decide what plants you want to grow hydroponically. Research their needs so you provide the best treatment and nutrients for the species you're working with. An incredible resource that can help you decide is this USDA page on hydroponics, which offers a detailed list of helpful links.
To get you started, here's a quick list of hydroponic plants that are relatively easy to grow.
Best Plants for Hydroponic Systems
Here are some flowering plants that you should enjoy success with. Be careful when growing flowers hydroponically - you may end up for more than you bargained for. Some of the best plants for hydroponics gardens are:
Vegetables and Fruits
Growing hydroponic lettuce and strawberries and tomatoes is very popular, especially in soils and climates where these fruits and veggies don't grow well outside. When you grow fruits and vegetables hydroponically, expect them to ripen more quickly and yield in greater quantities. When starting out, try some of these:
- Green Bean
Building Your Own?
If you do decide to build your own hydroponics system, check out these free hydroponic garden plans put out by NASA. (Yes, hydroponics in space is big. As they say, in space, there's not a lot of space, so hydroponics would be an essential part of any human settlement in space.)
Here's another set of free hydroponic system plans offered by NASA and designed for high school students.
Garden Care Tips
- Keep your hydroponic garden clean by removing debris. This reduces the risk of fungi infecting your medium.
- Use a hydroponic cleaner to remove grease stains and salt build-up from the pumps, light fixtures, growing area, pumps and other equipment.
- Keep your hydroponic garden well ventilated.
- When insecticides are called for in your hydroponic garden, use different insecticides each time, to avoid the insects' becoming immune to them.
- Choose bush versions of vine-growing plants like tomatoes and green beans. Bush plants tend to wander less than vines.
- Prune diligently to control your hydroponic plants' wanderings and to optimize their growth.
- Don't over-water your hydroponic garden.
Indoor Lighting: Artificial Daylight in the Home
Many indoor hydroponic units need lighting systems to bring enough light for photosynthesis and plant growth.
The blue hydroponic light kits you see use metal halide to encourage plant growth, while the red lights using high pressure sodium provide a gentler complement, rather than substitute, for natural sunlight.
Hydroponic Lettuce Gardening YouTube Video
Hydroponic vs. Soil: Who Will Win?
© 2009 Chris Telden
elegantfarmer on June 23, 2020:
Nice blog especially on hydroponic tech
Randal Walton on May 16, 2020:
Am building a nutrient film system using 4" water pipe and 3" cups. The cups are about 1" above the water. Is this normal or should I use 3" water pipe so the cups set lower? Thanks in advance
Kenneth C Agudo from Tiwi, Philippines on March 07, 2015:
Wow thisis great. I am planning to have my own hydroponic design for my undergraduate thesis. Hope it will be good :D I love this idea. I am so in to it. So obsess!
Brian Dooling from Connecticut on January 22, 2013:
awesome hub, very informative! Im very curious about hydroponic gardening, especially as a way to grow fresh greens all year round. That vertical/solar hydroponic garden picture is awesome! I'm assuming if you grow tomatoes or cucumbers in an indoor hydroponic garden you would have to hand pollinate the plants? great hub voted up and sharing!
Maximizer from San Jose, Costa Rica on August 06, 2012:
I've been getting into aquaponics recently, which is pretty much the same thing as hydroponics except the nutrients for the plants come directly from fish waste (which are also grown in the same system). That knocks out two of those disadvantages right there.
conradofontanilla from Philippines on July 09, 2011:
One good potting medium in hydroponics is coconut coir dust or coconut peat. It decays slowly if at all, meaning it does not react with the minerals you supply your plants.It also absorbs a lot of the solution and releases it slowly, in a way lessening evaporation.
Chris Telden (author) from Pacific Northwest, U.S.A. on May 06, 2009:
Thanks for your comment, Peggy! No, this was the product of lots of research, and I'd love to try it, but my toddler won't let me free long enough to do anything like a hydroponic garden. I'd love to hear if anyone has done it, though.
Peggy Woods from Houston, Texas on May 06, 2009:
Afraid I'm gardening in the soil, but this was certainly interesting. Are you gardening the hydroponic way?