Frequently Asked Questions

Frequently asked questions (FAQ) about lawn irrigation systems and how efficient they are at water conservation. Water conservation requires foresight, which very much includes the planning for how lawn irrigation systems will be installed.

What are the pros of automatic lawn irrigation systems? Aren't they wasteful?

What equipment is required for automatic lawn irrigation systems?

What’s the difference between “spray” lawn sprinkler heads and “rotor” heads?

Why should differences between types of sprinklers matter in lawn irrigation systems?

What are "drip" lawn irrigation systems and how do they promote water conservation?

What are “irrigation zones" and what's their role in lawn irrigation systems?

How does soil type affect lawn irrigation systems?

There are three different types of soils.... How do I find out my soil type?

How can rain sensors work with irrigation timers in lawn irrigation systems?

Is sprinkler installation a do-it-yourself project?

What's the cost for professional installation of lawn irrigation systems?

Question: What are the pros of automatic irrigation systems? Aren't they wasteful?

Answer: Automatic irrigation systems are convenient, especially for those who travel. If installed and programmed properly, automatic irrigation systems can even save you money and help in water conservation. Dead lawn grass and plants need to be replaced, and that can be expensive. But the savings from automatic irrigation systems can go beyond that.

Watering with a hose or with an oscillator wastes water. Neither method targets plant roots with any significant degree of precision. Automatic irrigation systems can be programmed to discharge more precise amounts of water in a targeted area, which promotes water conservation.

Question: What equipment is required for automatic sprinkler irrigation systems?

Answer: To simplify matters concerning irrigation equipment, we can speak of four basic components of automatic sprinkler irrigation systems: the timer or "controller" (sometimes misspelled "controler"), irrigation valves, underground piping and sprinkler heads. Drip irrigation systems have equipment that discharges water differently and will be covered separately. Even among sprinkler irrigation systems, there are various types of “head” equipment for discharging water. “Spray” heads and “rotor” heads are two of the most common.

Question: What's the difference between "spray" lawn sprinkler heads and "rotor" heads?

Answer: Two common types of lawn sprinkler heads are “spray” heads and “rotor” heads.

Spray lawn sprinkler heads are sometimes designed to pop up out of the ground when the sprinkler system is activated, while others rest on pipes that remain aboveground at all times. Spray heads discharge a large volume of water in a relatively short amount of time, giving them, in irrigation lingo, a “high application rate.” For this reason, sprinkler systems with spray heads are most suitable for even surfaces, not slopes. If you do have to use a spray head on a slope, program your sprinkler system such that water is discharged over several shorter periods. This will help you avoid wasteful run-off.

By contrast, rotor lawn sprinkler heads have a lower application rate, so they’re simpler to use on slopes. Rotor heads also apply water more uniformly than do spray heads, making them more suitable for watering larger areas. For people who wish to irrigate large areas of lawn, sprinkler systems with rotor heads would be a logical choice.

Question: Why should types of sprinklers matter in lawn irrigation?

Answer: Whether you use spray head sprinklers or rotor head sprinklers for a particular area in your lawn irrigation does matter, because of the difference in application rates.

Above all, be consistent in the types of sprinklers you use (i.e., spray head or rotor head) within specific areas. Mixing head-types within the same area leads to over-irrigation of some parts of your lawn just to get adequate amounts of irrigation to other parts. The goal of lawn irrigation is to target water distribution as precisely as the system allows.

Question: What are drip irrigation systems and how do they promote water conservation?

I'll explain drip irrigation systems briefly below. For a detailed explanation please consult "Drip Irrigation."

Answer: Drip irrigation system, at the most basic level, are constituted by a series of tubes that have holes opened along them at intervals. For a further description of drip irrigation systems, please continue reading....

The location of the open holes is tailored so as to irrigate most efficiently the specific garden beds in which drip irrigation systems will be buried, promoting water conservation. If you have a bed in which perennials are spaced at two-foot intervals, then there will be corresponding holes in the tubing at two-foot intervals, through which water will be discharged. You don’t waste any water with drip irrigation systems, because you’re not watering the intervening area between plants. The dripping occurs only where the plants are stationed.

Sprinklers, in contrast with drip irrigation systems, spray water into the air first, before it ever reaches the ground. Wind can carry airborne water away, distributing it elsewhere than where it was intended to go -- an inefficiency not conducive to water conservation. Drip irrigation systems preclude this unnecessary water loss by taking the water right to the roots.

Drip irrigation systems are often installed in areas in which flowers or shrubs are growing (i.e., individual elements with spaces between them), as opposed to a lawn. Drip irrigation systems allow you to target plant roots even more precisely than do sprinklers, resulting in better plant health and better water conservation.

Question: What are irrigation zones and what's their role in landscape irrigation design?

Irrigation zones are an element of landscape irrigation design that allows to target water distribution with precision, thus cutting down on waste and saving you money.

Answer: The premise behind the landscape irrigation design concept of "irrigation zones" is simple enough. Before you install your system, you need to decide that area A of your land should get X amount of water, while area B should receive Y amount, etc. Once you have irrigation zones established, you will then program your system accordingly. This is one of the virtues of automatic irrigation systems: you can target water distribution more precisely than by manual watering or by using oscillators.

The demarcation of landscape irrigation zones is an issue to consider when planting – well before irrigation design itself. Establish separate beds for your plants according to how much water they need. If plants with similar watering needs are planted together, you’ll conserve water. You’ll also promote plant health by insuring that one plant isn’t over-watered on account of one of its thirstier neighbors. This planting strategy is sometimes referred to as "xeriscaping." Drought-tolerant shrubs will inhabit one landscape irrigation zone, drought-intolerant annuals another, and so on. The lawn is a landscape irrigation zone all by itself. An area with southern exposure requires more watering than one with northern exposure.

Question: How does soil type affect lawn and garden irrigation?

Answer: Your soil type will affect your regimen for garden irrigation, both for purposes of plant health and conserving water. Sandy soil types dry out quickly. Think of them as being like sieves. They require more frequent watering than do clayey soil types. For more on soil types, please continue reading....

You’ll waste water on sandy soil types if you apply too much all at once, since the water will percolate quickly through the porous earth – right past the root zone. Once water passes the root zone, it is useless. For plants in sandy soil types, program the timer for your garden irrigation to release water over several short periods.

Plants in clayey soil types should also be watered over several short periods – but for a different reason. You need to give the water time to soak into the earth. If you water too much all at once, water just runs off and is wasted. Because clayey soil types retain water well, not only can you get away with watering less frequently, you positively should water less frequently, lest you drown your plants’ roots.

Question: How can rain sensors work with irrigation timers for water conservation?

Answer: Plants get thirstier in summer than during spring and fall, so program your irrigation timer accordingly, rather than always keeping the irrigation timer on the same setting. This will promote water conservation, as will watering at the right time of day and overriding irrigation timers with rain sensors.

The time of day when you irrigate is a factor in water conservation. If you program irrigation timers to go on early in the morning, you’ll lose less water to evaporation than if you were to irrigate in the heat of the day.

For optimal water conservation, it will be necessary to override the irrigation timer of your automatic system, if your area receives heavy rains the night before your system is programmed to run. You’d only be pushing up your water bill unnecessarily. If you’d rather not have to bother overriding your system manually in such cases, install a rain sensor on your roof. Rain sensors can be tied into automatic systems, shutting them off for you after a period of rain.

Question: Is Sprinkler Installation a do-it-yourself project?

Answer: Installation of sprinkler systems should be handled by professionals, unless you’re good at making complex calculations. If you do decide on a do-it-yourself sprinkler installation, acquaint yourself first with whatever inspection codes for irrigation your town may have.

Drip irrigation systems, on the other hand, can easily be installed by do-it-yourselfers.

Question: What's the cost for professional irrigation installation?

Answer: The cost for professional irrigation installation will depend on the size and complexity of your lawn. But for the average lawn, having a sprinkler system professionally installed should cost $2000-$3000.