A drip irrigation system doesn't just save water (and the money you pay for that water), it also saves time. No more getting up early to sprinkle your tomatoes: with an automatic system, your vegetable garden is fully watered by the time you've had your first cup of coffee. No worries on vacation: the petunias around your patio will stay lush and lovely, sufficiently irrigated even when you're away.
Time Required: 4-8 hours
- Start with a small drip irrigation system: A vegetable garden laid out in rows or a flower bed on a terrace are both perfect for drip irrigation systems. Shrubs around your house foundation or hedges at your property line also can be watered efficiently with drip irrigation.
- Determine a water source: Any outdoor faucet can be used for an automatic drip irrigation system, provided you attach a Y-shaped valve hose connector, which can be found at a hardware store. Put it on upside down, so that the bottom of the "Y" attaches to the faucet. Attach one arm to the garden hose that will deliver water to the system. The other arm can be attached to an auxiliary garden hose for other watering needs.
- Start measuring: Draw a garden plan, showing the plants you want to water and how far apart they are. Each plant will get an emitter -- a tiny sprinkler (often a bubbler or a slow drip-drip one) for its own watering needs, and each will be attached to the water source with a network of drip irrigation lines, 1/4" and 1/8" plastic tubing that runs from the main hose to your plants. You'll want two emitters for plants that need lots of water, such as tomatoes, hydrangea, rhododendron or evergreens. For help with the design, check out Jess Stryker's excellent website, IrrigationTutorials.com.
- Gather your gear: You'll need a battery-operated timer for your system, which can be set like a clock to automate watering times. A pressure regulator / back-flow valve is essential to prevent the water from backing up and ruining your household plumbing. Hose adaptors help, as do optional items such as a filter to keep rust and dirt out of the drip irrigation line and a fertilizer injector.
- Assemble the drip irrigation lines first: Lay the tubing out in the sun to soften the plastic, so it's easier to work with. Cut the 1/4-inch tubing with scissors, and push the ends into the connectors to extend the lines toward your plants. Use the 1/8-inch emitter lines to connect the main lines to the emitters.
- Connect the flow from the faucet: Connect the remaining equipment from the faucet in this order: Y-connector, timer, back-flow/pressure unit, hose-thread adapter, garden hose, another hose-thread adapter, and drip irrigation line. Your water supply is now linked to your system's main 1/4-inch line.
- Test the drip irrigation system: Toggle the switch on the Y-shaped connector so water will run from the faucet to your system. Set the timer on manual, and then set it to On. Turn on the faucet. If you've done this correctly, you'll see the emitters start to spout like tiny fountains. Adjust the amount of water by adjusting the flow from the faucet. The emitters shouldn't look as though they are bursting or straining, but neither should the water flow look too flat.
- Check for leaks: When you're satisfied with the water flow, turn the timer off but leave the faucet turned on. You should hear the water stop running. This is the time to ensure there are no leaks between the faucet and the other equipment. If there is leakage, you are probably using the wrong adapter -– it should have a hose-type threading, not a pipe-type threading. Leaks around connectors or emitters usually can be fixed with a bit of tape.
- Set your timer: Twenty minutes once a day is usually enough. Experiment with different amounts of watering time until you’re satisfied your plants are receiving adequate moisture.
- If the thought of piecing together a bunch of plastic tubes isn't your idea of fun, San Francisco-based Urban Farmer Store and Gardener's Supply Company in Vermont sell complete drip irrigation systems for small gardens and patio containers.
- Alternatively, you can install a soaker hose. Snake this porous hose, available in 25- or 50-foot lengths, around roses, flowerbeds or shrubs; hide it with mulch. The far end is capped, and the water just oozes out slowly for a good, deep watering. You will still need the back-flow valve/pressure regulator unit to prevent the water from backing up into your home, and you can attach a timer to further simplify things.
What You Need
- Y-shaped hose connector for the faucet (also called a hose bib)
- A timer for your drip irrigation system (battery operated)
- Pressure regulator/backflow valve
- Garden hose (15-, 25- or 50-foot length)
- Hose-thread adaptors
- Main drip irrigation lines - 1/4" plastic tubing that can be cut with a scissors
- Assorted connectors – tees (T-shaped) and elbows (right angles)
- Emitter lines – 1/8-inch plastic tubing to run from main lines to emitters
- Emitters – One to two per plant, or spaced 10 to 18 inches apart
- Tape measure