Hydroponic gardening may sound like a futuristic idea but it is not. It is part of hydroculture, the practice of growing plants only using water with a growing medium and nutrients. There is no soil involved.
With the technology available today, we can grow our favorite plants, or any plant for that matter, at any time of the year. With the latest hydroponic systems along with specialized horticultural lighting, indoor gardening becomes easy and effective. If plants receive the water and nutrients they need at their roots, they can grow exceedingly well without soil. When these plants are food, they can feed the world by producing more and better quality plants than soil-based farming can produce.
There are early examples of hydroponic gardening such as the Hanging Gardens of Babylon built in the 7th century BC by King Nebuchadnezzar II for his wife according to ancient Roman and Greek writers. The plants in the garden were not rooted in soil. An elaborate, if primitive, irrigation system would have been required to keep the plants alive.
Marco Polo mentioned the Floating Gardens of South China in the 13th century. The gardens may have existed as early as 304 CE.
There are also Egyptian hieroglyphics that show farmers growing plants in water. In the first century, the Roman Emperor Tiberius used what is considered an early form of hydroponics to grow cucumbers out of season by using mica instead of soil.
The Floating Gardens of the Aztecs were also grown on water. They were developed in the 10th and 11th centuries, and in 1519, when Cortez discovered what is today Mexico City, it was the best-fed city in the world. Since it was surrounded by water, the Aztecs built floating gardens that transformed the wetlands around the city into an area that could be cultivated. Today, these floating gardens are considered a work of genius engineering.
In the 17th century England, hydroponics began to be taken seriously with several books written on the subject starting with Francis Bacon in 1627. He wrote about growing plants without soil. In 1699, John Woodward discovered that plants grown only in water did best in water that had been mixed with soil and strained than in distilled water.
In 1929, in the United States, William Gericke of the University of California at Berkeley grew 25-foot tomato plants in his backyard without soil. He publicly promoted hydroponics and as they say, the rest is history.
Hydroponic systems are generally classified as active or passive. Active systems need pumps and other mechanical devices to move the nutrient solution to all of the roots in the garden. These systems are usually recovery systems that continuously reuse the same nutrient solution. They require electricity and will not work if there is a power outage unless there is a backup power source.
Passive systems are the easiest to set up and maintain. They do not require pumps or moving parts and are considered the best option for beginners. The nutrient solution is absorbed by the plant medium and goes to the roots. One drawback is that the roots are always wet and may not get enough oxygen. This may be solved by the medium used, as some are more porous than others are and allow more oxygen to the roots. For example, perlite tends to repel water and hold oxygen. Another possibility is to use a nutrient solution that contains dissolved oxygen.
There is more than one way to grow plants without soil. Many of us may think of plants with their roots dangling in the water, but this is just one method. It is called nutrient film technique (NFT) and has several variations that are used all over the world. These systems are popular commercial systems and have long channels where the nutrient solution is constantly flowing along the bottom of the channel. At the end of the channel, the solution goes into the main reservoir and is cycled through the channels again. There are other methods such as drip, water, wick, ebb-and-flow and aeroponic.
A drip system is a popular form of hydroponic gardening in which the plants are suspended in a substrate or growing medium and are fed a nutrient solution that is stored in a reservoir. A pump and timer are required to move the nutrient solution. The pump is run at regular intervals by the timer so the nutrient solution is gradually dripped on the roots of each plant through a drip line. Any nutrient solution that is not absorbed by the roots can be collected and returned to the reservoir. A non-recovery system does not recover excess nutrient solution, so the pH in the reservoir does not vary. If a recovery system is used, the pH in the reservoir needs to be checked regularly and adjusted.
The water system is mainly effective for lettuce. It involves immersing the roots in water that contains the nutrient solutions. An air pump oxygenates the water to allow the roots to breathe.
The wick system is considered the simplest type of hydroponic system. It is called a passive system because the nutrient solution and water is moved by a wick to the roots. The plant’s roots are suspended in a growing medium such as perlite, which is expanded volcanic glass, or coconut fiber over the nutrient solution and wicks made of fiber or rope soak up the nutrient solution and carry it up to the roots.
The ebb and flow system may be the least popular type but it is very effective. The plants are in a tray of growing medium, which is flooded with nutrient solution. There is a cycle of flooding and drainage. This is considered a versatile system because a variety of growing mediums can be used.
The Aeroponic system is considered very high-tech. The growing medium is usually air. The roots hang in midair and are misted with the nutrient solution. Misting occurs every few minutes or the roots will become dry. A timer is required to control the pump to produce the mist. This is the most high-tech system and is not recommended for first-time gardeners.
There are many advantages of hydroponic gardening starting with the fact that you are no longer subject to growing seasons. You can grow plants at any time of the year in less time. Even though hydroponics is based on water, it uses about one-twentieth of the amount of water required for traditional gardening and the water can be reused multiple times.
Since there is no soil, the maintenance of a hydroponic garden is much less because there are no pests, weeds, soil-borne diseases or fungi and no harsh chemicals required to treat these things. The gardens are compact and take up much less space than traditional gardens and harvesting and planting are much easier at the waist-high levels.
If you are just beginning to be interested in having your own hydroponic garden, this video may inspire you.
It shows how one person can set up a garden and grow vegetables and herbs quickly and easily in their own home.
Almost any plant can be grown with hydroponic gardening. Lettuce, herbs, chard and kale are good plants for beginners. Basil, sage and chives are suitable for small indoor systems. Tomatoes, cucumbers and bell peppers are successfully grown in hydroponics.
In order to grow watermelons and strawberries, more space and care may be needed. Many different fruits and melons have been successfully grown. However, corn, root vegetables and vining plants may not be suitable for small systems.
As the world population increases demanding more food, hydroponics is in the unique position of offering high quality, non-GMO, organic produce that is fast and easy to grow. One way of meeting future food demands is by growing plants without soil. This is already being done in habitats that do not normally sustain plants through hydroponics.
Hydroponic farms can change from pesticide-based growing to organic growing almost instantly, where soil-based farms require three years to make the transition in order to be certified as organic.
Lighting is another important factor of hydroponic indoor gardens, and new technologies in lighting such as ceramic metal halide systems, double-ended bulbs, wavelength-specific fluorescents, LEDs and induction systems are becoming more widespread in the hydroponic industry. When starting a small hydroponic indoor garden, if you do not have enough natural light for the size of your garden, you may need artificial lighting.
Hydroponic gardening is not expensive to set up and can provide delicious produce, all year long. They are becoming more and more popular as individuals and corporations see that the world population cannot be fed by traditional, soil-based farming. As herbicides and pesticides contaminate the water and soil, hydroponics shines as one of the best-growing methods for the future of agriculture.