Irrigation systems turn a chore into a breeze



Imagine this scene: it's August, in Houston. Temperatures have been hovering around 100 degrees for days and there is no forecast of rain. You watch your neighbor across the street drag water hoses around, note the uneven watering, the wasted water on sidewalks and street. But you, on the other hand? You've got an irrigation system, one that goes off and on by itself—delivering the right amount of water at the right volume at the right time in the right place.

Irrigation systems provide both convenience and peace of mind. Just as important, they help maintain the health of your landscape. No rain? No problem. Irrigation systems are designed to be a substitute for natural rain, helping you save water, time, energy and money.

It's All About Control

Why is an irrigation system so important to your garden landscape? It helps you control the correct amount of water to the appropriate plant material. It allows your landscape to be separated by zones into lawn, bed and color areas that require different watering conditions due to varying plant materials and sunlight conditions. Additionally, it utilizes controller box technologies, such as timers, time delays and rain sensors, that let you set an automatic schedule for your landscape needs while, at the same time, allowing you to switch to manual for the inevitable, unexpected events.

Anatomy of an Irrigation System

A good irrigation system uses a combination of heads, controller technology and zones to create a site-specific system for your garden landscape.

• Rotors are water heads that work well in large areas like lawns. Rotor is the term used to describe the various sprinklers that operate by rotating streams of water back and forth over the landscape.

• Pop-up spray heads were designed for smaller or irregular spaces such as landscape beds. These small heads often produce a fan-shaped pattern of water.

• Drip irrigation and bubblers are perfectly suited for trees, rose gardens, pots, planters and urns.

• Controllers can be quite sophisticated these days and come with different programs. The best ones are outfitted with a pressure vacuum breaker (PVB) that safeguards the irrigation system against allowing any contaminates to be suctioned back into the city's drinking water when water pressure drops. Rain sensors and water delay options prevent over-watering of your plant material during times of natural rain.

Plot Lines

Proper head spacing within an irrigation system is crucial for proper watering coverage. This aspect is where the quality of an irrigation system is revealed. The calculation and specific measuring of head locations are important steps in providing even coverage.

The water pressure in most residential systems isn't great enough to water an entire lawn at one time. As a result, most systems are divided into zones, each with its own control valve. Control valves are operated by an electronic controller that turns each zone on and off according to the schedule you set. The cornerstone equation of a quality installation goes like this: good coverage and lots of valves equal great control.

Getting Started

When putting in an irrigation system, plans and permits are required by some cities. It is also important to call for utility line locations. Otherwise, it can be expensive to repair any resulting damage.

If you're installing an irrigation system in an established lawn, trenches should be hand-dug so as not to disturb any lines and wiring, including landscape lighting wiring. The grass should be set aside, but replaced as soon as possible after installation. The grass may yellow, but it usually re-establishes itself quickly.

During the construction of a new home, the tree preservation plan may include a temporary irrigation system to water the trees during construction, which sometimes can last a few years. “A temporary irrigation system and hand-digging to minimize damage to trees and their root systems are a very important part of tree preservation,” explains Jeff Halper with Exterior Worlds.

Keep It Going

Ongoing maintenance is another critical aspect of an irrigation system. Since the system is both mechanical and electronic, it will require regular care, such as the replacement of broken heads and stuck valves. Before working with any contractor, it is advisable to understand what kind of landscape maintenance service they offer after the installation.

Also, you will need to monitor the times and days of watering, which will change depending on the weather and the season. “In Houston, the best time to water is usually between 3:00 a.m. and 5:00 a.m., which puts water on the plants and ground just in time for the sun to come up and start generating heat,” says Halper. “If you start any earlier, the water just sits there, giving fungus the opportunity to grow.”