Gardening Without Soil a Different Way of Gardening

Are you interested in trying a different method of gardening? Why not try your hand at growing plants without soil (hydroponics)? Hydroponics was once defined as "the cultivation of plants in water" and has been used for thousands of years. It is not a new science and its roots can be traced back to ancient China, Egypt and India, and as early as 600 BC in Babylon. Babylon known for its famous hanging gardens is listed as one of the Seven Wonders of the Ancient World. These gardens are filled with plants grown in a steady stream of fresh water rich in oxygen and nutrients that are regularly circulated. These gardens are also considered to be one of the first successful attempts in growing plants hydroponically.

Today hydroponics is referred to as the "cultivation of plants without soil." After many years of research and experimentation researchers determined that many different aggregates or media will support plant growth, therefore redefining hydroponics. It was discovered that plants would grow with the presence of nutrients, and that soil is not necessary for plant growth, other than anchoring the plant's roots. Plants can now be grown without soil using an inert medium, such as gravel, sand, or peat. To this medium a nutrient solution is added containing all the essential elements needed by the plant for its normal growth and development.

Growing plants hydroponically is not difficult if one understands the basic principles. Whether a plant is grown in soil or a soilless medium, there are many factors affecting plant growth and productivity. All plants require nutrients, water, light, and air to grow. A plant grown in soil obtains nutrients and water from the soil, when available. With hydroponics, because water and nutrients are always available, the plant is never stressed. Sunlight and air are readily available in an outdoor hydroponic system. However, for an indoor system, one must provide an adequate light source and good air circulation. Metal halide lamps, sodium vapor lamps, gro-lights, or fluorescent lights used in conjunction with incandescent bulbs provide adequate light. The expense of running a light source is exorbitant and should be considered.

Plant roots must have oxygen available to keep them alive. Healthy roots (which are white in color) are responsible for the uptake of all nutrients into the plant. If the roots die, it is impossible for the plant to survive, even if plant growth requirements are met. Air circulation around leaves is important since it mixes the air and allows the plant to draw out the carbon dioxide necessary to carry on photosynthesis. Air circulation also helps prevent fungal diseases caused by moist, stagnant conditions. Indoor units often have a small fan to circulate the surrounding air.

The nutrient solution is the most important factor in the success or failure of a hydroponic system. Most fertilizers commonly available in garden centers do not contain all of the 13 elements necessary for plant growth because the growing media usually provides many of them. Hydroponic plants receive nutrients from a different source; so it is necessary to use a fertilizer formulated for hydroponic systems. Hydroponic fertilizers are available from many mail order companies and a few specialty garden centers. It is important to follow the dilution rate recommended on the label and to test the solution to be sure that the pH is between 5 and 6. Simple pH test kits and pH modifiers are available wherever fish supplies are sold.

Depending on the stage of plant development, some elements in the nutrient solution will be depleted more quickly than others. Because of this, it is important to change the nutrient solution every two weeks. The old solution can be used to water other houseplants or outdoor plants. Also, make sure that the nutrient solution is kept at the original volume. As water evaporates from the nutrient solution, the fertilizer becomes more concentrated and can burn plant roots. Add water only and not more fertilizer to raise the nutrient solution back to its original volume.

This method of soilless gardening offers many advantages to the home gardener. The labor involved in tending your plants is markedly reduced. Since a sterile medium is used, there are no weeds to remove, and soil-borne pests and diseases are minimized, if not eliminated completely. Properly grown hydroponic plants also are healthier and more vigorous because all of the necessary growth elements are readily available. The plants can mature faster, yielding an earlier harvest of vegetable and flower crops. Hydroponic gardens also use less space since the roots do not have to spread out in search of food and water. This small space requirement makes hydroponics ideal for home gardeners, and it makes better use of greenhouse space.

Some home gardeners are using hydroponic techniques to grow flowers, ornamental plants, and fresh vegetables year round. If the grower decides he wants to change to a different crop after the harvest, it's a simple matter to do so. Another plus is that growing does not have to be done on a seasonal basis. Crops can be started so that a continuous supply of most any vegetable or fruit can be obtained at any time of the year.

There are many systems available to growers but on a commercial level such as the Aggregate System or the Water Culture Systems they are very expensive. The non-circulating system, or non static container method system is simple and relatively inexpensive compared to the other conventional hydroponic methods. This system is applicable for the hydroponic hobbyist who is just starting out. There is no need for mechanical aeration and/or circulation and thus, electrical power is not needed. The lower portion of the plant roots are immersed in nutrient solution and these roots specialize in nutrient and water uptake. The upper portion of the plant roots are suspended in the humid air above the nutrient solution and these roots specialize in oxygen uptake.

For the plant hobbyist, hydroponics offers an opportunity to learn more about the growth of plants and their interactions with their environment. If a person is willing to work and apply him or herself, plants can be grown hydroponically by a complete novice with no past experience at growing crops. Marcy Stanton, a Master Gardener with the UNH Cooperative Extension has been experimenting with hydroponic gardening for many years using the non-circulating system. She is offering a workshop open to the public for a fee of $5.00 per person to defray any expenses incurred. Her discussion will focus on growing plants using a simple, non circulating hydroponic system. You will learn how to set up a low-cost basic system and be able to take home supplies to get your own system started. It's fun and easy and you can grow plants even if you were born with a "brown thumb". So join her and other interested gardeners on August 12, 2003 at the Family, Home & Garden Education Center in Manchester, NH. The time is 7:00 to 9:00 PM. Early registration is recommended because space is limited.

For more information or directions call the UNH Cooperative Extension's Family, Home & Garden Education Center's Info-Line toll free at 1-877-398-4769 for "Practical Solutions to Everyday Questions." Trained volunteers are available to answer your questions Monday through Friday from 9:00am to 2:00pm.

Rachel Maccini, Coordinator Family, Home & Garden Education Center University of New Hampshire Cooperative Extension, Hillsborough County