Traditional irrigation directs water into furrows next to planted rows of crops. This system relies on gravity, water pressure and osmosis to deliver the fluid to the roots. Its main drawback is inefficiency. Water is lost below the root zone, not enough flows down the row, only one side of the plant gets most of the water, and some is lost through evaporation. A hose-based watering system uses a fraction of the fluid of traditional irrigation. Making the switch to drip irrigation involves the design and assembly of a few basic components.
Draw a sketch of the areas that need water. Note where the water sources are, and the distance to the foliage. Mark the plants that have particularly high or low water needs as well; the system can be adapted to accommodate them. Write down what type(s) of soil the system will be watering. Illustrate where the main line(s) will go to reach foliage. Generally, a main line should not exceed 400 feet, or have emitters feeding off of it that exceed 220 gallons per hour. Consider what drip rate emitters should have, based on soil type and plant water needs. Design tutorials are available online, such as IrrigationTutorials.com and Rain Bird's Do-It-Yourself page.
Attach the backflow preventer, in-line filter and pressure regulator to the hose bib (faucet) that will be the water source. The backflow preventer keeps water from the drip system out of the household water supply. The filter keeps out particles that could block the water lines, and the pressure regulator ensures proper water pressure for the system to work well.
Attach the main line from the hose bib assembly, and run the line alongside each group of foliage to be watered. Punch subsidiary lines into the main line, and run each along the base of each row of plants. Cut to the lengths needed; fold over the ends and slide cuffs to hold them closed.
Install in-line emitters on the subsidiary lines where they will drip closest to the roots of the plants. Once the emitters are in place, turn on the water to ensure that fluid reaches all the plants correctly.
Expand and adapt the system as needed. Drip watering systems change easily to meet evolving conditions. Many accessories are available to accommodate ground cover and seed-start watering needs, foliar spray needs, changes in plant spacing and other new developments, not all of which can be anticipated. Familiarize yourself with the equipment and make changes as necessary.