Intro to Hydroponics

What is hydroponics?

History

Commercial Hydroponics

Growing Systems and Methods

Hobby Hydroponics

Learning More

Hydroponics is the science of growing plants without soil. Plants need nutrient elements such as Nitrogen, Phosphorus, Copper, Iron, Boron, etc. to grow properly. Plants use water to transport the required nutrient elements through their roots to feed the rest of the plant. These nutrients are traditionally obtained from the soil. The plant roots grow out searching for nutrients and the water to take them up. Soil typically does not include the proper balance of optimum nutrients and moisture levels. Hydroponics is all about enriching water by creating and maintaining a "nutrient solution" that is perfectly balanced for the plant. When the plant gets exactly what it wants all the time, it will grow as fast, and provide the best flavor and nutritional value, that it possibly can. Absolutely anything that can be grown in soil can be grown hydroponically. The key is determining the the precise, ideal, nutrient solution for the specific plant, and consistently providing it to the roots. Typically, by using a general purpose hydroponic nutrient, plants will outperform soil grown plants in the same environment.

Some of the benefits of hydroponics include:

• Healthier Plants- Plants grown hydroponically are generally healthier than their soil grown counterparts, since they receive a near-perfectly balanced diet. Additionally, the plants rarely come in contact with soil-borne pests and diseases.

• Healthier Consumers- Without the use of herbicides, fungicides, and pesticides, the resulting produce is healthier to eat. Additionally, agricultural workers are not exposed to toxic chemicals, and labor costs are reduced.

• Higher Yields- Since hydroponic systems reduce water and nutrient stress to the plants, crops grow faster and can be grown closer together without starving each other. Perfect plant conditions results in perfect plant production.

• Conservation- Hydroponic systems conserve water by preventing evaporation and runoff. Losses due to drought and flooding are significantly reduced as well. Regions where water is scarce, or without adequate soil conditions, can grow crops hydroponically.

History

Hydroponics is not a recent invention. Historians have found Egyptian hieroglyphics depicting the cultivation of plants in water as far back as several thousand years B.C. The Hanging Gardens of Babylon and the Aztecs Floating Gardens of Mexico City are both examples of early hydroponic gardening. Modern hydroponics made major advances in the 1930s. W.F. Gericke coined the term hydroponics from the Greek "hydro" or "water" and "ponos" or "working." Literally, water working. Hydroponics has evolved through the use of various growing media such as sand, gravel, rockwool, coconut fiber, etc. to bare-root systems such as Nutrient Film Technique (NFT) and Aeroponics. Since launching massive amounts of soil into space is cost-prohibitive (as well as dumb), hydroponics is, and will be, used to grow plants in space.

The science of hydroponics began with experiments to determine the elementary nutrient requirements of plants and how plants processed those elements. That knowledge has evolved into the desire to automate the delivery of the precise nutrient mix to the plant to optimize the growth and quality of the plants. Further, the fine tuning of varying the nutrient mix not only for specific plants, but also the varying nutrient mix for the specific stage of growth. For example, we know plants use more Nitrogen during the green growth phase, and more Phosphorus during the flowering and fruit production stage. Additionally, the plants will adapt and do what they can to survive when subjected to less than ideal conditions. These less than ideal conditions slow down the growth, and can seriously affect the quality and flavor of the plant.

Commercial Hydroponics

Hydroponically grown produce is available at all major supermarkets across the country regardless of the season. In North America, 95 percent of greenhouse vegetables are grown hydroponically.The hydroponic greenhouse industry is valued at over $2.4 billion dollars and is growing at 10% per year. The industry is expanding because it is economically productive. Controlled environments and controlled growth techniques maximizes production and is much less labor intensive. in addition, the resulting produce is clean, healthy, and nutritious, and growing hydroponically significantly conserves the earth's resources.

Increased yields, improved and more consistent quality, and elimination of herbicides and pesticides, are major advantages of using hydroponic growing methods for commercial food production. Because hydroponics is almost always used with controlled environments such as greenhouses, the additional major benefit of extending or eliminating growing seasons provides continuous crop production, which again provides extensive increases in productivity.

Runoff of phosphates, fertilizers, and pesticide residues from large commercial farms have a serious environmental impact, especially on groundwater contamination. By greatly reducing the use of agrichemicals, hydroponics is environmentally friendly and results is safer vegetable crops as well. The economic viability of using hydroponics for commercial crop production became evident in the 1930's. The first economically viable commercial hydroponic systems were used to produce greenhouse-grown tomatoes, cucumbers, lettuce, and herbs. These, along with peppers, are still the mainstays of commercial hydroponic vegetable production.

Hydroponic systems were quickly applied to cut flower production where increased yield and soil sterilization were major issues. Initially, the production of bedding plants and potted flowering plants moved from a soil based system to a "soilless media" consisting of a blend of peat moss vermiculite and perlite. Next, fertilization moved from mixing fertilizers in the soilless mix to applying nutrients dissolved in water, basically hydroponics. The application of these hydroponic techniques saved on water and fertilizer and resulted in more uniform crops. More recently, the use of sophisticated flood and drain systems and crop specific nutrients means that virtually all potted flowers and bedding plants grown in the United States utilize some form of hydroponic technique.

back to top

Growing Systems and Methods

Commercial systems can be divided into two classes, bare root systems and substrate systems. Many different methods can be used for a variety of crops. Bare root systems include nutrient film technique (NFT), deep flow, and aeroponic systems. Deep flow and aeroponic are the most popular for commercial lettuce and herb production. Susbstrate systems use a media such as rockwool or perlite. Other substrates include peat, coir, sand, and technically any other media that, specifically, is not soil. Although flood and drain and NFT systems are sometimes used, drip irrigiation with rockwool or perlite is the most commonly used method for the production of tomatoes, peppers, and cucumbers, as well as cut flowers. Flood and drain systems are mainly used in the production of potted flowering plants and bedding plants. Although very popular with hobbyists, aeroponics is rarely used in commercial greenhouse production.

Hobby Hydroponics

Hydroponics in the home provides the pleasure of growing plants and reaping the benefits of home grown, fresh produce all year long. Knowing your tomatoes and other vegetables have never seen weed sprays or pesticides can be very reassuring, but faster growth and great taste have to be the best part. The hydroponic hobbyist enjoys designing, building, and experimenting to improve the methods and performance of systems. For the hobbyist, hydroponics is a highly technical specialized form of agriculture that has an ever expanding application to everyday use. At the same time, home hydroponic gardens have become so simple that people without a green thumb can be very sucessful in growing flowers and vegetables in their homes. Home hydroponic systems allow home gardeners to grow the hottest pepper, or to enjoy the same tomato flavor they first experienced when Grandpa handed them their first vine ripe tomato in the garden.

Learning More...

There are plenty of great resources available for gardeners who want to know more about hydroponics, organics, and more specific areas such as the use of CO2, H.I.D. lighting, or cuttings (clones). Check out our links page or browse the books we have available.