Drip irrigation greatly reduces water use by delivering moisture to exactly where it is wanted in the garden. By selecting different lines for different emitter rates, thirsty plants can get more water at the same time the drought-tolerant get less, making it much easier to automate watering for the whole outdoor property area.
A variety of components are available in drip watering systems, some of which are necessary in almost all home systems; others vary by garden and plant types.
Main Line Components
Gardeners design the drip system starting from the main water source(s), usually an outside faucet. Keeping the lines free of any particles, however small, is absolutely critical, so a filter connection is highly recommended.
A pressure regulator ensures that home water pressure won't be too high to cause damage to the system. A single main hose line usually connects at this point, to bring the water to the vicinity the plants.
Smaller tubes that feed off of the main line generally do the work of taking the water to the individual plants. Generally, the feeders attach to the main line by tapping in with a simple punch tool. The central line can alternatively branch off from a main hub with a number of outlets.
There are a number of different ways the water reaches the plants from the subsidiary lines, depending upon the manufacturer and specific plant needs. Basic in-line drip emitters rated to leak at specific rates, usually measured in gallons per hour, work for established plants. Just cut the line, insert the emitter where it will reach the base of the plant, and reconnect the line.
End attachments like the drip hose, sprinkler hose, and sprinkler attachments are useful for seed beds, ground cover and close-spaced plants. Different manufacturers have variations on these themes to account for direction of flow, density of spray, etc.
Tees and elbows for all line sizes allow the gardener to bring the water wherever it's needed, and to branch lines as necessary. Caps and simple fold-over insert tubes end any sized line. Spikes with attachments lend whatever height is desired for water to reach over tall plants. U-shaped wire pressed into the ground over a line holds it in place on the soil to ensure that the water goes where it's supposed to.
In-line shut-off valves are useful to temporarily turn off the water to an area, like where onions and potatoes are curing in the ground. Timers take the work out of having to remember to turn the water on and off. All these accessories allow the system to be highly adaptable, repairable and expandable as gardens change and components age.
Putting It All Together
Draw a picture of your garden and the kinds of plants in it. Draw where the main line(s) connect to your water source(s) and how they'll reach plant groupings. Draw lines to serve plants of similar water needs and determine the best emitter-types to deliver that water. Take a rough measurement of the total lengths needed of each type of line, and quantify the number of each type of emitter you'll want. Besides a good water filter and regulator, chances are you'll want a few wire stakes to hold the lines in place.
If there are other accessories that make sense for your particular environment, jot those down, too. Then go shopping. Don't be too concerned if you have to go back for more or exchange something; the beauty of most drip systems is that they're highly adaptable and can be changed anytime.