Georgia averages about 50 inches of rainfall per year, which is more than enough to supply the total water requirements of most plants. However, this rain does not always fall in sufficient quantities during the time of year when it is most needed by the plants. In order to maintain a lush green lawn and productive garden, supplemental water in the form of irrigation is often needed during peak water use periods.
Two basic types of irrigation are suitable for the home landscape: sprinkler irrigation and drip (or trickle) irrigation. Numerous types of sprinklers are available, and if selected properly, they can be adapted to cover almost any shaped area. Sprinklers are usually the best choice for vegetable gardens and turf areas. Drip irrigation has been increasing in popularity during the past few years and is especially suitable for watering individual plants such as shrubs and trees. Some types also work well with row crops grown in the garden.
An irrigation system may be as simple as a sprinkler connected to a water hose, or it may be a complicated system of underground pipelines with multiple circuits and automatic controls. A step-by-step design procedure is not always a simple matter. A number of factors are involved. With sprinkler systems especially, the types and number of sprinklers must match the pressure and volume capacity of the water supply. Also, the application rates from sprinklers and drip emitters should be low enough to prevent excessive runoff from the soil surface but high enough to supply the water requirements of the crops. As a result, it is often a trial and error procedure to select the best sprinklers and/or emitters and spacings for a particular system.
Several factors must be known in order to begin planning an irrigation system:
* irrigation needs of targeted crop or plants;
* shape of the area;
* soil type (intake capacity);
* water source;
* operational requirements (hours per day, automatic or manual controls, etc.).
Sometimes the water supply already exists, and the system must be designed with the pressure and volume limitations in mind. In other instances, the water source requirements will be determined from the irrigation design, and the water supply installed accordingly. At any rate, you must consider all of the preceding factors in planning an effective irrigation system.
If you are planning an irrigation system for your garden, lawn or landscape, stop by the Extension Office at 116 Main St. to pick up a copy of Irrigation for Lawns and Gardens. This publication explains in laymen's terms how to cope with many of the factors that have been mentioned in this article.