Any person who comes in contact with an irrigation system affects its efficiency. Whether its the initial landscape or irrigation designer (for obvious reasons), or a landscape maintenance contractor who maintains the landscape, we all play a role in optimal uniformity and timing of irrigation schedules.

As a landscape's foundation for success, design of plant material and irrigation seems the logical place to start. The first rule is to attempt to group plant material in hydrozones, or plants with similar water needs. In addition to matching basic irrigation requirements, consider root depth, maturity, slope, rainfall, wind and sun exposure and maintenance.

• Curved margins where turf and hardscapes meet can be elegant, but face it -- sprinklers will always spray in a linear pattern. If curves are part of the landscape design, incorporate buffer zones to capture and use overspray. Retrofit difficult areas into perennial beds with drip or other low-volume irrigation.
   
• Slopes create unique irrigation scheduling (percolation) problems. Unless you are willing to cycle and soak your zones and adjust schedules often, avoid turf on slopes by using perennial groundcovers. Also, consider terracing to reduce or eliminate slopes. Triangular spacing on small turf areas relies on overspray. Even the best irrigation manager can't keep water out of the street when a compact landscape utilizes triangular head spacing.
   
• Consider hardscapes and structures in your irrigation design. it's easier and cheaper to design and install an irrigation system that oversprays pathways, decks and walls and fencing. Every square foot of watered hardscape can shed more than 25 gallons of irrigation water every year. This is more than a waste, it also increases the potential for liability for pedestrians and even traffic.
   
• Use permeable fabrics instead of plastic for weed barriers. Runoff is already an irrigator's enemy, as it wastes water and erodes the landscape, why layout an impenetrable barrier to water and increase the likelihood of runoff?
   
• Pressure regulation is a simple, effective way to ensure that water droplets are leaving sprinkler orifices in the consistency for which they are designed. Too much pressure and droplets atomize and float away with the wind or evaporate. Too little pressure and your arc and radius of throw is severely inhibited, also dramatically affecting uniformity. Remember that a zone operating at 48 percent efficiency takes twice the water to keep a "green" landscape.
   
• Do not ignore topography. Organize zones and space heads properly for elevation and relief, again ensuring that areas in the landscape with similar needs are grouped accordingly. Watch the placement of backflow preventers on sloped sites. Atmospheric vacuum breakers shadowed by moguls won't cut it. Too often, landscape and irrigation designs were made from a drafting table, by people unfamiliar with the site.
   
• Another site-specific obstacle to efficient irrigation is obstructions. Tree trunks, poles, signs, benches fire hydrants all should be considered in the design or installation. Less obvious but equally draining on efficiency are sunken heads and overgrown plant material. Keep all sprinkler heads to grade and keep the shrubbery and trees well groomed and out of the trajectory of sprinklers. Overhanging limbs and branches stifle uniformity and create runoff. Obstructions create plant stress and water waste and can significantly damage property.
   
• Always use the minimum dimension of an area to determine the maximum radius of the heads. There's nothing wrong with large rotors on a 50-foot spacing . . . unless the width of an area is only 35 feet. Imagine overspray from a large turf head drumming on your bedroom every morning.

Form alliances with local professionals whom you trust and respect. We've all become so specialized that we tend to forget we work in landscape management. It's not the designer's fault that the installation contractor didn't follow or understand the blueprints. Likewise, it's not the contractor's problem if the designs call for a head spraying into an obstruction. Neither is it the landscape management crew's fault if someone shreds a head that was installed too high. Everybody's reputation is at stake, and the client gets stung. Consider offering comprehensive service and avoid "finger-pointing".

* When you get down to it, efficiency means getting the most for the least. Sometimes efficiency is more expensive to install, but cheaper to maintain. While many modern electromechanical clocks can be programmed in one- or two-minute intervals, there are still some models that only allow programming in five-minute increments. Suppose the watering needs and precipitation rate merit a runtime of 17 minutes. Some of these clocks only provide 15- or 20-minute runtime options. Which would you choose? If you choose the 20-minute cycle you are using almost 18 percent more water than you would with a 17-minute cycle. But the alternative is stressed plant material that won't make the client happy. The accuracy of some electromechanical timers is questionable. Before specifying or installing an electromechanical timer, be sure that it will deliver dependable accuracy.

Finally, good old-fashioned irrigation system maintenance will boost and sustain peak efficiencies. First, always employ a rain shutoff device with your controller. Nothing angers the public, or the client, more than irrigating while it's raining. Replace heads with like heads, ensure heads are to grade, replace worn nozzles, check pressure at the head, check for weeping valves and inspect low-volume emitters for plug. These regular "heads-up" activities can be performed with the everyday motions of landscape maintenance and they all can save time, money and plant material. Maintenance also means regularly adjusting irrigation schedules. Depending on your location, this means weekly, monthly or, at the very least, quarterly.

As a consumer of natural resources, it is everyone's obligation to effectively manage their use. It saves your client money and you from headaches, while making your services more professional. Do more than make it efficient -- make it known that it's efficient, and you'll see your business grow.

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