Why Use an Irrigation System?
Weather patterns are changing and it is now not uncommon for weeks to pass without a single drop of rain. Yet most plants need an inch of water per week in order to thrive. That means gardeners must supplement nature by providing additional water.
Irrigation systems are more effective and less time-consuming than hand-watering or sprinklers. They put the water at the base of the plants, rather than on the leaves, and provide a more thorough soaking of the plant's roots. This is a more efficient way to water and it is better for the plants.
Overhead watering wets leaves, which can pro-mote fungal diseases. The splashing of water from plant to plant can spread both pests and disease. Timers allow the gardener to control the amount of water, when watering occurs, and for how long.
Kinds of Irrigation Systems
Two major advancements have increased the use of irrigation systems during the past two decades: computerized timers and improved soaker hoses.
Computerized timers have become cheaper and more sophisticated, giving the user numerous options for programming water from the faucet throughout the growing season.
Slightly less expensive are irrigation systems which, while not computer activated, operate on the timer principle. Set by a spring-loaded valve, this type of timer can be set for two hours of watering and used in conjunction with a soaker hose, which is sold separately. Though less costly than a fully computerized timer, with this system the user must be on the premises to set the timer. The beauty of the fully computerized irrigation system is that you don't have to be in the garden with a hose, wielding a sprinkling can, or setting up a sprinkler.
A computer timer enables the user to regulate watering when the user is away from home. The gardener can be comfortable in the knowledge that the computer-timer will do its job whether it is once a day for an hour or once a week for three to four hours. They are great time-savers.
Below-Ground Irrigation
The advantage of below-ground irrigation is that it puts moisture uniformly under the ground, whereas above-ground systems may lose water to evaporation. It also provides water at a low rate of flow, insuring the water will not run off.
Once installed, the system is virtually maintenance-free. Fertilizer can be added if required, and the system will tolerate chemicals.
Below-ground systems can be used in orchards, vegetable gardens, and flower beds. These systems are flexible enough to be set up to cover an entire flower bed, or scaled down to water individual flower pots.
One system consists of polyethylene tubing with injection-molded emitters welded to the tubing. The emitters guarantee a flow that will accommodate a constant rate of high or low pressure water flow.
The tubing comes with a variety of insert fittings including couplings, tees, elbows, in-line shutoff valves, filters, pressure regulators, and, if desired, a timer. These systems can provide seven to ten years of problem-free use. However, the line should not be exposed to the sun.
Another below-ground drip line system is a 5/8-inch diameter tube that is a blend of rubber and polyethylene that will not crack, decay, or be damaged by freezing. With this type, the moisture "weeps" out of the tube.
To install below-ground irrigation, you must dig a four-to five-inch-deep trench, place the tubing in the trench, secure it with special pins, replace the soil, and cover it with three to four inches of mulch. Because the tubing is flexible, it can be laid in close proximity to plantings.
The installation should be plotted on a map of the garden to show where drip-line connections were made and the positions of drain endings. (The latter is important as the line must be drained for the winter.) You must also be careful not to accidentally run a spade or other garden implement into the buried tubing.
Above-Ground Irrigation
These irrigation systems, many of them computerized, are generally used with soaker hoses. The hoses are placed on top of the ground and covered with several inches of mulch.
Once the system is in operation, water oozes out of the soaker hose and wets up to three feet on either side of the line, giving a six-foot-wide band of water.
To install this type of system, a battery-operated computerized timer is attached to a faucet and a soaker hose is attached to the bottom of the timer.
The computer can be programmed to water every day for three or four hours at a specific time and to shut off at a specific time. It can be programmed to run every other day or once a week.
After it has been programmed, the computer will operate at that precise setting for the life of the battery. The computer can be bypassed by hitting the "on" button, which permits watering even though the timer is set.
Soaker hoses, which are an integral part of the system, come in various lengths, with 50 feet being the average. The better types are made of recycled rubber. There are no definitive holes, just a porous extrusion from which the water oozes.
