Choosing a Sprinkler System for Your Lawn
by Ruth S. Foster
If you think you've had it with hauling hoses to cope with drought, maybe you think it's time to consider a sprinkler system, especially if your precious green lawn is often tan and spotty from lack of water. If you have some big bucks to spare and are willing to spend some time comparison shopping, it's not necessarily a bad idea. For a beautiful green lawn, my first choice would be an ancient Roman slave in a toga, but my second choice would be the sprinkler. However be forewarned. Sprinklers are not simple, and if badly installed or poorly designed they will become a permanent maintenance pain. Let's begin with the options
Surface Drip Systems though short-lived, are cheapest and easiest to install. They're most useful for shrub beds, vegetables and flower borders.
The easiest is Leaky Hose, which is just that, a hose that leaks on purpose all along its length. You turn it on, and when you think it's enough, you turn it off. Problems are that it's hard to calibrate and it becomes brittle after cold weather.
More sophisticated is High Quality Tubing which can have attached emitters that go to each plant or pot. It takes some work and planning as to exactly where they should go. There are many companies that carry drip systems which can be laid on the surface or buried. The amount of water is regulated by the size of each emitter. They work best in frost free areas.
Netafim Techline has tubing with holes 12 or 18 inches apart which emit a calibrated half gallon of water per hole per hour. It comes with a line water pressure adjuster, automatic timer, connectors and T-joints, as do all quality drip systems.
Problems are that all sprinklers have to be blown out with compressed air before winter in cold climates, and breaks have to be mended (with connectors) as needed.
Underground Sprinklers are what most people are familiar with, especially for the lawn. They are almost always the choice in northern areas.
I checked out some costs in the Boston area in 1999, though prices will vary considerably depending on the climate and area you live in. In Boston, expect a professionally installed system using high quality parts to cost from $1500 to $2500 for a 2500 square foot front lawn. (100' x 25' or 50' x 50'). "Whoa!" you say , "That much?" At $2000, it breaks down as follows. About $500 is for the plumbing connection, a decent electronic controller is about $300, piping and heads about $500 and labor adds another $700. It would take 3 people one day to install in a northern climate, possibly less in warm areas. To add another 2500 square feet in the back might cost only $1000 more.
Yearly maintenance costs include re-adjusting the sprinkler heads, and trouble-shooting. In cold climates, the system has to be blown out with compressed air so the pipes will not freeze and burst, and then turned on again in spring.
Water is an additional cost. Water costs can be much higher if a sewer charge, based on water use, is added, so many towns allow sprinkler systems to have a separate meter (about $85 + cost of installation). Some people drill wells which produce water of adequate quality for plants but not for human use.
Ask Lots Of Questions There are some things to check out before you sign on the dotted line. Most important is the design. It involves an analysis of your water pressure, picking the right components, keeping beds and lawn zones separate, and providing zone to zone coverage but without wasting water. Experienced installers can do it quickly, but ask to have it explained to you.
Check The Quality Of The Parts Most contractors don't use only one supplier, but might buy the controller from Rainbird, the pop-up heads from Hunter and the valves from Weathermatic. How long is the guarantee period? Cold winters are hard on sprinklers.
Ask About The Controller Prices range from $80 to $400. A good one should be able to set different zones for different schedules per week. There must be a manual override so you can turn parts off and on when you wish. And there should be a rain sensor to turn it off when it rains and so conserve water.
How Much Water, How Often, And On What? Don't let your sprinkler company set your timer by their mantra universal setting which is for golf putting greens in Arizona (a little each morning). Short, frequent waterings encourage shallow rooting, diseases and low tolerance to stress, like drought and heat.
The proper sprinkler settings for Cold Temperate Climates are:
Grass About l hour per zone, once a week (This should be about l" of water. To check, put out a glass and measure the depth. The soil should be wet about 6 to 8 inches down. Use this also for newly planted trees and shrubs.
Flower beds 20 minutes every other day.
Impatiens 5 minutes, 2 x per day.
Old shrubs and trees only need water when it doesn't rain.
In Tropical Or Desert Areas sprinkler settings depend on your particular climate, such as humid Florida or dry southern California.
How Can You Tell When The Grass Needs Water? When walked on, the footprints remain visible for several minutes. When the grass blades don't spring back, it means wilting is imminent so manually turn on the water long enough to supply a full inch.
In Northern Climates When it's, very hot and windy during summer, to prevent lethal, especially with bluegrass varieties, one may turn on the sprinkler for about 5 minutes during mid-day to syringe and cool off the grass blades.
The Best Time Of Day To Water is very early morning. Then the grass will be hydrated during the heat of day, and the individual grass blades will have time to dry off and not get fungus diseases.
When To Have A Sprinkler Installed Ideally during the growing season so it can be fine tuned right away. If you put it in during fall, it may not be under warrantee if problems crop up the second winter.
Do-It-Yourself Kits There are homeowner sprinkler kits. Parts for 2500 square feet cost about $800, the controller around $100 and you supply the labor. Good if you know plumbing and have big, strong hands because the parts are stiff and tricky to put together. Design is complicated so get help where you buy it. Also one needs a strong back because there is a lot of digging and bending.
The Biggest Problem with all underground sprinklers is if they are not installed deep enough, especially do-it-yourself systems. If too shallow, they can be punctured with an edger or a lawn aerator. Also frost heaves can push pipes to the surface which may trip someone or be damaged by the mower. In northern areas, six inches is a minimum, 8 is better, commercial installations may be 10 inches deep.