Applying the water Sprinkler and drip systems
Sprinkler heads and drip emitters are the end of the line for the system; they deliver water to your plants. Sprinklers spray water overhead and are supplied by a system of underground pipes. Drip emitters apply water very slowly, fed by tubing that's installed between the soil and the mulch. I explain both in the following sections. Refer to the later section, "Applying Sustainable Watering Concepts to Your Permanent Irrigation System" for more on how to sustainably use sprinkler and drip systems.
Even though sprinklers are inefficient compared to drip, they do a good job of watering a lawn or meadow or large areas of low ground cover (although a sustainable landscape wouldn't take this approach in the first place). In these cases, do everything you can to make the sprinkler system as efficient as it can be.
Select a type of sprinkler head that's appropriate for the circumstances. Note that heads come in aboveground and pop-up versions. Here are some popular types of sprinkler heads and how they're used:
✓ Spray heads: Small areas are best served by spray heads, which cover up to a 15-foot radius from the head. The spray head has a fixed nozzle that delivers a fan-shaped arc of water in a circular pattern.
- Rotor heads: Rotor heads have a gear-drive mechanism that delivers water via rotating streams, putting the water down more slowly and evenly than spray heads do. The coarse streams are less apt to blow around in wind. Rotors are used for larger areas because they shoot water over longer distances — a radius of 20 to 40 feet or more.
- Impact heads: Impact heads use a swinging arm to break a stream of water into a wider pattern. This old-fashioned design is quite efficient, though rather noisy. (A sustainable garden should be a quiet garden.) Impact heads are used the same way as rotor heads.
Never mix different types of heads on one valve, because coverage patterns and precipitation rates can vary considerably.
A well-designed, properly installed drip system can be one of the most sustainable features of your landscape, saving lots of water and making the plants truly thrive. Consider the following:
- Drip systems apply water via emitters, which are small, precisely engineered openings that keep the flow consistent from one emitter to the next.
- Emitters can be installed on or molded right into polyethylene drip tubing; the latter arrangement is better because the emitters stay put.
- Each emitter dribbles out water at a very slow rate — usually XA to 2 gallons per hour — and the water soaks straight into the soil without being sprayed into the air.
- Filtration is essential to the longevity of the system, because even tiny bits of grit in the water can plug the small openings in the emitters. Wye-type filters with 150-mesh screens are the best. (Certain types of water can clog emitters even with proper filtering, so check with your water district to be sure that drip will work with your water.)
- Drip systems operate at 20 to 30 pounds per square inch (psi) of pressure. Because this pressure is much lower than the incoming pressure for most water systems, small pressure regulators especially made for drip systems are required at each valve.
- Elevation changes can affect the accuracy of delivery, resulting in more water going to low spots. If you have more than 3 to 5 feet of elevation change within the area served by one zone valve, either split the system into high and low sections or use pressure-compensating emitters, which handle elevation changes better than standard emitters do.
- Drip tubing usually is installed on the surface of the ground and covered with mulch, but some types can be buried beneath the soil surface. Tubing is fastened to the soil with drip staples, which should be installed every 3 feet to prevent the tubing from popping up through the mulch.
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How would you like to save a ton of money and increase the value of your home by as much as thirty percent! If your homes landscape is designed properly it will be a source of enjoyment for your entire family, it will enhance your community and add to the resale value of your property. Landscape design involves much more than placing trees, shrubs and other plants on the property. It is an art which deals with conscious arrangement or organization of outdoor space for human satisfaction and enjoyment.
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