U of A University of Arkansas Division of Agriculture Research and Extension University of Arkansas System

Pictures of chickens, flowers, wheat, a boy looking through a magnifying glass, irrigation pipe, soybean pods, and fruits and vegetables.

Cooperative Extension Service

Cooperative Extension Service

Agricultural Experiment Station


Search | Publications | Jobs | Personnel Directory | Links
County Offices | Departments

About Us

Find Us

For the Media

Agriculture

Business & Communities

Families & Consumers

Health & Nutrition

Home & Garden

Arbor Day
Commercial Horticulture
Composting
Control of Disease, Insects, and Weeds
Fruits, Nuts, Vegetables & Herbs
Gardening Calendar
Gardening with Janet Carson
Landscaping
Lawns
Master Gardener
Plant of the Week
Your Home

Links
Newsletters
Publications


Natural Resources

4-H Youth Development

Public Policy Center

For Faculty & Staff

Giving

Dale Bumpers College
of Agricultural, Food &
Life Sciences


Division Home


Agricultural Experiment
      Station Home


Cooperative Extension
      Service Home

 

Picture of a sprinkler watering a flower bed.Sprinkler Systems

Sprinkler systems are a wonderful tool for successful gardening, especially in hot, Arkansas summers.  But just because you have one, doesn’t mean you can ignore it.  Older systems may need some upgrading.  Sprinkler heads get clogged, damaged or broken and plants suffer.  Although we have had more than our fair share of water so far this season, heat is upon us and drier conditions will more than likely be in our future.  Planning now can insure a successful gardening season.

Did you know that on average, 60-80% of all water used by a household is water that is used to irrigate lawns and gardens?  To have a thriving garden in Arkansas, you have to have some form of irrigation system, whether that is an in-ground system or simply dragging a hose.  Sprinkler systems are a wonderful tool and can make your watering job easier, but if they are poorly designed or maintained you could be wasting water, which means wasting money. 

Maintaining an irrigation system

Picture of different types of sprinkler headsIf you have an in-ground sprinkler system, your first step is to test it. Manually run your sprinkler system as you start it each season.  Monitor the amount of water coming out of each head.  Make sure you don’t have any sprinkler heads that are dribbling or shooting geysers, or heads that are spraying water into the street or driveway.  Check for runoff.  If water starts running down the street soon after the system comes on, the volume is too strong. Knowing the range of your heads is important, because sprinkler heads need to have an overlapping pattern to make sure that all areas of the landscape are getting the same amount of water.  One easy way to test this is to place tuna cans randomly in the sprinkler zone and turn it on.  Time the spray for 15 minutes and then measure the water in all the cans.  If there is a huge difference in rates, your system needs help.  Even if everything seems to be going out as planned, if your system is more than 5-10 years old, water efficiency has drastically changed with sprinkler heads and you could save up to 30% in water savings just by replacing older, less efficient heads. They are continually making improvements on the materials which increase the durability of sprinkler heads while decreasing their costs.  Advances in nozzle design can decrease overspray and runoff and reduce susceptibility to losses from wind.   

If you are starting from scratch, you get the option of choosing where your zones of watering are. Water zones are how you break up your property for watering purposes.  There isn’t enough water pressure to water every inch of your yard at once, so you need to break the yard up into zones.  Typically each zone should contain plants with similar water needs. It is wise to keep lawn areas separate from shrubbery beds, since different heads distribute different amounts of water.  You may be drowning your shrubs or under-watering a lawn area if the zone is mixed.  Putting in your own system is doable, but can be a lot of work.  Take measurements of your yard and plot out flower beds and lawn areas.  Then take this plan to a reputable sprinkler company and let them help you create a plan.  In addition to the plot layout, you need to know what kinds of plants you want to grow, the soil type, slope, sun or shade and hopefully the water pressure and water source.   

Picture of flexible tubingPicture of old rigis pipingIf you have sprinkler heads that need to be replaced, this is an easy do it yourself project.  Dig carefully around the existing sprinkler head, using caution as you near the water line.  If you dig too freely, you may cut sprinkler lines, which means more work for you.   If your old heads are on swing joints, you simply unscrew the old head and replace it with a new more efficient head.  If they are on older rigid tubing, you will have a little more work, but you should replace the tubing which holds the head to flexible tubing called a swing joint. If you run over a spray head with a lawn mower or a car and have used a swing joint, the risk of damaging the pipe or fitting in the ground is not really an issue because the material is flexible and will give with the impact.  The swing joint literally moves or swings out of the way when objects such as a car or lawnmower impact the sprinkler.  To add a swing joint and install new heads you will need some tools. Tools you need are: Teflon tape, PVC glue, utility knife or plastic pipe cutter, then the swing joints, new sprinkler head and nozzle. Again, sprinkler experts can help you decide which nozzles are right for your situation.   

Step 1: Turn off the water to the sprinkler system at the meter.  
   
Step 2:  Locate and dig around head down to where the head is connected to the supply pipe.  (Be careful not to damage pipe or possible wires located around the head)

Picture of someone digging around a head.

   
Step 3:  Unscrew old head trying not to get dirt or debris in the pipe. Picture of a pipe with a rag in it to keep dirt from getting inside.
   
Step 4:  Place first threaded connector onto the supply line.  Use Teflon tape on all threaded connection, this will prevent water from leaking at these connection points.

Picture of PVC glue

Picture of someone putting Teflon tape around the threads of the pipe.

   
Step 5:  Adjust the length of the swing pipe as needed.  Use utility knife to cut the pipe and reconnect it to the connection point.   
   
Step 6:  Firmly connect the new head to the swing pipe.  The other end of the swing pipe can be connected to the fitting on the supply line.

Picture of someone putting on a new sprinkler head.

   
Step 7:  Place new head in the correct position and cover only ¼ of the way with dirt.  Turn on water and inspect the head for leaks as it is running.  
   
Step 8:  Place new head at the correct depth and replace dirt around it.   

Once the new head is working it is time to adjust it.  Depending on the type of sprinkler head it should come with a specialized tool from the manufacturer.  In some cases a small flat screwdriver will work as well.  This tool will control the arc of the spray so you can adjust the area that it will cover.  Also use this tool to adjust the pattern to fit the specific area; if your area calls for a full circle, half, or quarter you can adjust the pattern to avoid over spray into the street or driveway. 

Try to make sure that the sprinkler head is at least two inches in from the edge of any curb, sidewalk or other surface you will maintain with a power edger. If you place the head directly against the edge, an edger or weed-trimmer may damage it.  Install the sprinkler heads where they are even with the level of the soil, not to the level of the turf or higher. If the sprinkler head is too high, your lawn mower will cut it or damage it every time you mow.

There are four basic types of sprinkler heads: pop-up spray and rotor heads, impact rotors, gear-driven rotors and large turf rotors which are for commercial golf courses and large fields.

One of the most common types of sprinkler heads in the home landscape is the pop-up head.  Pop-up spray heads are designed to supply a continuous stream of water.  There are a variety of nozzles that can be used which have a variety of distribution patterns that you can set to meet the landscape needs. Pop-up spray heads are designed to cover relatively small areas with a spray radius of between 3 to 15 feet. 

Impact rotors are designed to cover larger areas than pop-up spray heads; the spray radius for most rotors is 20 to 150 feet.  These are the heads that we automatically think of when we hear the sound of an older system, because when they are running, they can be quite loud when the swinging arm strikes the body of the rotor.  You can set the spray pattern from as little as a 40 degree angle to 360 degrees. 

Many impact rotors are being replaced by gear driven motors. Their closed body design prevents dirt and other debris from getting in and clogging them up, and their low cost, quiet operation and versatility make them a popular option. These gear-driven rotors have a radius that ranges from 18 to 55 feet and an arc rotation from 40 to 360 degrees.

Another upgrade:

Picture of controller with rain sensors mounted above.A worthwhile addition to your sprinkler system is a rain sensor.  New technology in sensors can produce 25% water savings.  These are easily installed with new or older systems.  They are usually located near the controller of your system and monitor the rainfall.  This prevents the system from coming on when it is raining.  Everyone has seen it pouring down rain and the sprinkler system is still running.  This is a waste of water and money. 

Now that your system is up and working, don’t set it to run daily.  Know the water needs of your yard and use it efficiently. Watering deeply, but infrequently is best.  To insure that the water penetrates the soil instead of running off, divide the length of time each zone runs in half, and run through the whole system twice.  Avoid watering during peak demand times—5:30 a.m. to 7:30 a.m. When everyone is showering, doing a load of clothes, or running the dishwasher, water pressure may not be at its peak.  Do try to water early in the day to allow the water to get to the root zone of the plant before they need it and to avoid losing water to evaporation or wind. You can water from 3:30 a.m. to 5:30 a.m. or 7:30 a.m. to 10:00 a.m. Avoid watering at night.  Having wet foliage at night can lead to disease issues.  Test your system again mid-summer. 

Avoid watering during afternoon hours. Water is lost to wind and evaporation

 

Back to Irrigation


© 2006
University of Arkansas
Division of Agriculture
All rights reserved.
Last Date Modified 02/10/2012
Webmaster

University of Arkansas • Division of Agriculture
Cooperative Extension Service
2301 South University Avenue
Little Rock, Arkansas 72204 • USA
Phone (501) 671-2000 • Fax (501) 671-2209
 

MissionDisclaimerEEO
PrivacyFOI