Drip Irrigation Explained


Drip irrigation--sometimes called micro irrigation--has its roots in parts of the world with harsh climates and limited water supplies. As modern materials became available in the 1960s, farmers discovered that using drip irrigation increased crop yields while lowering water use. Modern drip irrigation is now a well-accepted method of irrigating both commercial and home gardens.


Because drip irrigation places water only where it is needed, over 90 percent of the water reaches the roots of the plant or plants. A drip irrigation system is, therefore, called 90 percent efficient. Conventional sprinkler systems range from 50 to 70 percent efficiency, meaning that 30 to 50 percent of the water evaporates or ends up in places that do not benefit the intended plants.


Drip irrigation systems are made up of regulators, hoses and emitters. Regulators help to limit the flow of water to certain parts of the irrigation system. The hoses deliver the water to the emitters. Emitters, in many cases, also act as regulators by limiting the amount of water delivered to a plant or planting area. There are two types of emitters. Pressure-sensitive emitters deliver higher water flows at higher pressures. The other type, pressure compensating emitters, provide the same flow, but over a range of pressures. Emitters are color coded to indicate flow rate. These color codes are not standard, so make sure your emitters are all made by the same company.


Emitters deliver water directly to the part of the plant that needs the water. This reduces water loss through evaporation, wind, overspray and runoff. Drip irrigation can also reduce problems with mold and mildew on plant leaves and stems. In some cases, mold and mildew are caused by excessive moisture on the green parts of plants. Drip systems can be automated with digital controls that can be either battery-powered or powered by your house mains.


Drip irrigation systems must be properly designed and installed. Improper design can lead to too few emitters or emitters that are placed too far apart. This will result in too little water reaching the roots of the plant. This can restrict root development. It can sometimes be difficult to tell if the system is working properly. An indicator that raises and lowers a flag as the system comes on can help with this situation.


Designing and installing a drip irrigation system is easier if you follow some guidelines. Start your systems with high-quality components. Inexpensive or poorly made components can adversely affect the performance of your entire system. You can use a single outside faucet for your drip irrigation system and other uses by installing a Y connector on your faucet. The drip system will connect to one part of the Y, and a hose for other purposes can connect to the other half of the Y.

Keywords: drip irrigation, low water irrigation, efficient irrigation

About this Author

Although he grew up in Latin America, Mr. Ma is a writer based in Denver. He has been writing since 1987 and has written for NPR, AP, Boeing, Ford New Holland, Microsoft, RAHCO International, Umax Data Systems and other manufacturers in Taiwan. He studied creative writing at Mankato State University in Minnesota. He speaks fluent Mandarin Chinese, English and reads Spanish.