HydroSeeding doesn't forgive bad coverage.

When it comes to sprinklers I'm pretty opinionated. That's why this is the longest page on my website. I think there's a lot of useful information here if you're willing to read it...

Back in the mid-1970's as a Landscaper, I got really excited about water hydraulics and decided to learn everything I could about the subject. But truth is, I was too much of a perfectionist to make any money installing sprinklers. If it wasn't right I'd make it right, even if it meant not making any money on the job.

After almost 14 years here in the Valley, I'm usually pretty busy HydroSeeding lawns. In answer to one of the most frequent questions, I don't usually install sprinklers any more - except every once in a while in the Winter months when it's slow. If you have questions after reading this page, I'll be happy to try to answer it for you.

   If you plan to hire a contractor or do it yourself, or even if you already have sprinklers, we strongly recommend taking a look at Jess Stryker's Sprinkler Design Tutorial before you ask us to HydroSeed your new lawn.

   If you already have sprinklers make sure they get the entire lawn area damp before they start making puddles.  If they can't do that, make an accurate "as-built" drawing of the lawn.  Show the locations of all of the sprinkler heads and the valves on the drawing.  Turn the sprinklers on one valve at a time and indicate on the drawing which heads go to which valves.

If you have pop-ups that don't cover well, very often just changing-out the nozzles to MP Rotators is enough to make an existing sprinkler system cover well enough to have a nice lawn.

   If you don't have sprinklers yet, make an accurate drawing of the lawn area showing trees and anything else that might affect coverage.

   Take a copy of your drawing to any Irrigation Supply Store in the Valley. (In the phone book under Sprinklers, Parts and Supplies you'll find Ewing, Horizon, Simpsons, Sprinkler World, Turf Irrigation, and several others.) If you walk in when they don't have a bunch of contractors waiting, Most will check your drawing and make suggestions to make it better or even design your sprinklers for you for free. Some charge a small fee for designing your sprinkler system, that they might give back if you buy the parts from them.

   Ewing Irrigation won't design your sprinkler system because their market is Landscape Contractors, not homeowners. But telling any Ewing Irrigation Store in the Valley you want to use Nature's Way HydroSeeding's Account will allow you to get contractor wholesale prices.

   If you decide to design your sprinkler system yourself, there are a few things I've learned over the years that might be helpful:

There's nothing more frustrating than discovering the sprinkler layout on the drawing doesn't actually match your yard.  Some sprinklers wind up being too far apart and others too close together.  That can lead to fungus in the wet areas and bare patches in the dry areas of your lawn.  It doesn't have to be that way.

Use 10 squares to an inch graph paper for your drawing.  (You can get it for free at most irrigation supply stores or in the sprinkler isle at Home Home Base or Home Depot.)  Don't draw the property lines first.  Lots aren't always square and houses are rarely square to the lots they're built on.  Draw the house on the paper first.  Then measure how far it is from the corner of the house to the edge of the driveway.  Then stand at the street and line up the side of the garage to a mark you'll make on the curb.  Then measure how far the driveway is from that mark.

Don't assume anything is square to anything else on your property. Use a string to extend the line made by the sides of the building to the property line. Get a can of upside down paint or a sharp stick and make a line in the dirt you can use for a reference.  Measure everything off of the corners of the house or those reference lines you make.  Swing an arc on the paper from known points to accurately plot the location of trees shrubs, existing sprinklers or anything else in the lawn area.  If you do it this way, your drawing will be a lot more accurate and you won't be surprised when your sprinklers don't cover evenly.

   It's a lot easier to make an accurate drawing than I made it sound. If I've confused you, look at Jess Stryker's advice for measuring your yard. Here's more of my advice:

We see a lot of sprinklers installed at 65% of the diameter of the heads. (15' heads 20 feet apart.) That almost always results in bare patches in the dry areas and fungus problems in the wet areas of a lawn (unless someone spends a lot of time hand watering the dry spots). 65% spacing just about guarantees you'll have a high water bill.

When heads are placed at 50% of the diameter (15' heads spaced 15' apart) the coverage is usually adequate in most of the yard, unless there's a little bit of wind when the sprinklers are running. Those lawns usually turn out OK. But still, fact is, we water for the brown spots in our lawns. It doesn't matter how even the coverage is in most of the lawn, most people will run the sprinklers as long as it takes to keep the dryest places in their yard green. Even with head to head coverage your sprinklers might waste a lot of water unless you hand water dry areas.

So how do we keep from having brown spots in our lawn without wasting water? It's simple. When the sprinkler heads are placed at 40% of the diameter of the heads (15' heads 12' apart) every square inch of the yard is covered by the water from 3 or 4 sprinkler heads from different directions. And the difference in the precipitation rate from the dryest to the wettest areas of the yard becomes incredibly even. And the sprinklers will only need to be run about half the number of minutes that head to head coverage would require.

But just putting the sprinkler heads closer together may not be enough to avoid problems. The rate of evapo-transpiration is a lot lower in shady areas. (That means shady areas need less water than areas in full sun.) Put the heads in shady areas on their own valves so you can run them less minutes or less often. That way you'll avoid creating puddles and fungus problems in your lawn.

After it's established, you should be watering every third morning. In the early morning hours, a lot of your neighbors will be watering their lawns and trying to take a shower and get a load of laundry going before they head off to work. But the water pressure is usually a lot lower in the early morning hours than during the day. Test the available water pressure and flow about 5:00 or 6:00 AM during the times you'll actually be watering your lawn after it's established. If you don't want to get up early to do that, then at least give yourself a good margin of error when you design the sprinkler system.

Even beyond that, you should give yourself a good margin for error. As the area becomes more established, the water pressure might be lower because there will be more houses using the same water supply. But that isn't the only thing that can lower the pressure. As pipes age, a layer of rough scale develops inside the pipe, causing it to be smaller and creating a lot more friction. That can also lower the water pressure substantually.

And unless you absolutely have to, don't even consider using a faucet on the back of the house to get water for the back yard sprinklers. Run a pipe from where the water enters the house (or even closer to the meter if you can) to the back yard. And consider up-sizing the pipe. I could give you statistics but I don't feel like looking them up. Take my word for it. You'd be lucky if 80 pounds of pressure at 18 gallons per minute at the front of the house gave you 30 lbs at 6 gpm at a back faucet. If you ran that it through 100 feet of 1-1/4" pipe you'd still have enough working pressure for 18 gpm. (But chances are If I had 18 gallons available I'd probably use 1" valves and design the system around 12 or 13 gpm.)

In other words, the larger the pipe and fittings, the slower the water travels. The slower the water travels, the less friction loss. Therefore, bigger pipe and fittings means more available pressure to the valves. The small diameter pipe and all the fittings under most houses creates enough friction loss to cut the pressure and flow to the degree that it's barely usable. That's why running a 3/4" schedule 40 pvc pipe around to most back yards is just plain stupid. Personally, I'd never use less than 1" schedule 40 pvc in front of a valve.

   Just for the heck of it, I'll throw a couple of other things at you.

2" pop-ups are stupid. If you go on vacation for two weeks, you might come home to a dead lawn if your sprinklers only pop-up 2". Unless you plan on installing Tifgreen sod for a home putting green, always use sprinklers that pop-up at least 4".

Sod comes with an inch of extra dirt, hydroseeding doesn't. Make the sprinkler heads flush, or at least make sure the sprinkler heads are low enough that your mower won't hit them.

If you have lawn next to a driveway (or even a patio or sidewalk) consider using double swing joints. Cut-off risers are fine in areas that aren't subject to a lot of traffic.

And by all means, make sure that the wires for the lawn sprinklers are before the wires for drip irrigation on the timer. If drip irrigation comes on first and runs for an hour when the lawn sprinklers should have come on, a lot of seed could burn up instead of germinating. If you're wondering which timer to buy, another section of our web site covers that.

   There can be a lot more to this stuff than people think. That's why I always recommend getting an Irrigation Supply Store to check your drawing.

   People often ask me what brands of sprinklers I recommend. That's a hard thing to do because there's a lot of good stuff on the market. But, I'll give it a shot.

Back when I installed sprinklers for a living, I used Rainbird 1804 series pop-ups for most small jobs. I like them for a couple of reasons. The orange colored caps that come on them make it easy to flush any dirt out of the system before you install the nozzles. Rainbird's pressure compensating devices made it easy to fine-tune problem areas or compensate for too much pressure. These days, Hunter SRS bodies seem to be more popular.

Whenever I had a situation where the water pressure was marginal I'd switch to Toro. Their small pop-ups use a little less water and handle low pressure situations a little better than Rainbird 1804's. But in my opinion Toro's pressure compensating devices suck.

That doesn't mean you should use Rainbird or Toro. I knew plenty of good Landscape Contractors (through my membership in industry associations) who swore by Hunter. The irrigation store I preferred to buy from didn't sell Hunter so I have no experience with their products. Even though a lot has changed in the last 20 years, those products are still the ones I most often see in people's yards.

Personally, I never liked impact sprinklers. For two reasons: First, they throw a lot of water long and a lot of water short, but in between the coverage really sucks. Second, unless you run full circle heads 4 times as long as quarter circles, and half circle heads twice as long as quarrter circle impact sprinklers, you'll never get uniform coverage. That's because a quarter circle impact will go back and forth almost 4 times in the same amount of time a full circle goes around one time. That means you have to valve impact sprinklers according to their pattern. That requires a lot more valves and a lot more pipe.

Gear driven rotarys have interchangeable nozzles. Instead of using a lot of extra valves, you can adjust the nozzle size to match the pattern so all the sprinklers have the same precipitation rate.

That doesn't mean I'm recommending long throw sprinklers or pop-ups. My personal preference used to be for smaller pop-ups. I think they give you a lot more control of how much water goes where. But even in average size yards that can mean a lot more valves. All those valves and pipe can make small heads a lot more expensive to use than large heads.

These days I strongly recommend MP Rotators for a lot of reasons: They are simply nozzles that retro-fit any conventional pop-up body, turning it into a very efficient rotor. They put the water on more evenly than pop-ups or single-stream rotors. They put the water on more slowly than most other sprinklers, giving it a chance to soak-in instead of running off. Their 3 sizes cover from 8' to 30' and have matched precipitation rates, so you can mix big ones and little ones on the same valve. That allows you to put a lot of them on a few valves.

   The people behind the counter at the Irrigation Supply Store can do a better job of helping you decide which sprinklers to use. That's because they sell this stuff every day and get a lot of information from manufacturers and feedback from contractors and homeowners. And most will be happy to explain the difference between the good commercial quality sprinklers and the cheap junk that hardware stores sell. And if they don't, go somewhere else.

They'll help you make a materials list and give you a price on the parts you'll need. Most will even deliver the parts. But if you're not comfortable with the first store you visit, go to another. (That's why I suggested making copies of your drawing.) It never hurts to get a second opinion.

And don't expect to get the right amount of fittings and pipe. 10 people could make a take-off of the same drawing and come up with 10 different parts lists. And none of them will exactly match what's used on the job. So buy extra pipe and fittings and make sure the store you buy it from will give you a cash refund when you bring back the extra parts. Some stores want to give you store credit on stuff you bring back. They force you to buy something you don't really want just because they won't buy back all the extra stuff they sold you.

   Paying a small fee to the Irrigation Supply Store for a drawing and parts list might be the best thing you could do if you plan to hire a contractor to install your sprinklers. Giving contractors a good accurate drawing to bid on means they'll all be bidding on the same job. If you talk to half a dozen contractors before you get a drawing made, they'll make you so confused you won't know who to believe.

   A lot of people ask me to recommend a good contractor. It seems like over the years every time I've done that, the guy I recommend winds up doing a lousy job for one of my customers. There's a lot of good, honest, qualified Landscape Contractors out there. And there are some whose qualifications are they can't keep a job, but they have a pick-up truck. And unfortunately, there are some who aren't so qualified, but are real good at getting people to part with their money. The best advice I can give about choosing a contractor is to learn as much as you can before you start interviewing them. And check out their references. And check with the Better Business Bureau to see if they've had a lot of complaints.

Personally, I'd be afraid of a contractor who stands in the middle of the yard and say's he'll put heads there, and there, and there, and there - without laying it out on a drawing first, or one who says his foreman will figure out where to put the heads they install the job. And I might be a little concerned about the guy who shows up in a brand new, top of the line truck. Is he making a lot of money because he's good, or is he just good at making a lot of profit at the expense of his customers?

    The knowledge you'll get by talking to a good Irrigation Supply Store can help you decide if the contractor you're talking to knows anything about water hydraulics. And if your existing sprinklers don't cover well, they can give you the name of a contractor certified to do a "water audit" and fix the coverage.

    But don't be afraid to install your own sprinklers. It'll cost 1/3 to 1/2 of what a contractor would charge if you decide to do it yourself. Except for filling in and tamping the trenches, most homeowners can install sprinklers in their back yard in a day. (But I'd recommend breaking it up into two weekends.)

   The store that sells you the parts should be happy to show you how they go together. (If they won't, buy the stuff from someone who will.) The Irrigation Supply Store can also tell you who does trenching in your part of town (usually for less than you can rent a machine). If wiring the timer and connecting to your water supply scares you, some stores will give you the number of someone who'll do that part of the job for you. (A lot of guys that work for big landscaping companies like those kind of side jobs.)

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Queen Creek, AZ 85242
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