Have you done an irrigation audit? There's a lot of helpful information in the irrigation section on this forum.

 

Have you done an irrigation audit? There's a lot of helpful information in the irrigation section on this forum.

I have not done an audit, but I'm going to do one next time I water. I have a proper rain gauge coming in the mail, but I think I can just try the tuna-can method in the mean time. I was pretty sure I was dealing with mostly fungus damage, but the nice green spots lead me to believe the rest of the yard could be nicer if it got enough water...

 

Have you done an irrigation audit? There's a lot of helpful information in the irrigation section on this forum.

I have not done an audit, but I'm going to do one next time I water. I have a proper rain gauge coming in the mail, but I think I can just try the tuna-can method in the mean time. I was pretty sure I was dealing with mostly fungus damage, but the nice green spots lead me to believe the rest of the yard could be nicer if it got enough water...

It can be a combination of both.

 

Are those heads lower than the rest of the system and do you know if you have a check value on those heads? If your spray bodies don't have a check valve and are downhill at all it could be leaking at those heads effectively drip irrigating those spots.

 

Are those heads lower than the rest of the system and do you know if you have a check value on those heads? If your spray bodies don't have a check valve and are downhill at all it could be leaking at those heads effectively drip irrigating those spots.

So they are Hunter PGP Ultra heads, and I'm not sure if they have check valves without ripping one out. They aren't downhill or anything, in fact one of the spots is actually on a ridge so it's slightly elevated. I went out and checked the areas to make sure they weren't soggy or mushy so I'm not suspecting any significant leaking. I can only water on certain days in my area so I will just update when I can do an irrigation audit tomorrow morning.

 

Are those heads lower than the rest of the system and do you know if you have a check value on those heads? If your spray bodies don't have a check valve and are downhill at all it could be leaking at those heads effectively drip irrigating those spots.

So they are Hunter PGP Ultra heads, and I'm not sure if they have check valves without ripping one out. They aren't downhill or anything, in fact one of the spots is actually on a ridge so it's slightly elevated. I went out and checked the areas to make sure they weren't soggy or mushy so I'm not suspecting any significant leaking. I can only water on certain days in my area so I will just update when I can do an irrigation audit tomorrow morning.

They sell PGP Ultras with and without a CV, so not sure. Just to be clear it wouldnt be a constant leak. Essentially without the CV the water in the irrigation line would potentially leak out well after after the zone had been turned off. It wouldnt be a ton of water, but for such a small area it may be enough to see more green in those spots. Just an idea.

Have you ever noticed that when you turn on one of those zones, it takes a few seconds for the heads to pop up? If so this could be an indication that the water has leaked from the line and it is taking a moment to refill and pressurize. With a CV the lines stay full it is pretty much instantaneous.

 

@gm560 I see what you're saying, and yes there's a bit of a pause when switching zones so you may be right. Also, did an irrigation audit, albeit a small sample (two cans spaced out in the back yard) but it was telling. There wasn't much water at all in the two cans (1/8" at most), and that was running the zone for a good 16 minutes. There's no way the backyard is evenly getting an inch a week. I'm going to up the watering a bit and keep moving the cans around to see how I'm doing. I might also mist more because I think a couple heads are kind of "throwing" water more than misting if that makes sense. Wish me luck!

 

Place the cans and run the system for 1hr. Yes 1hr. Then go measure. A few extra minutes are not going to make a difference + your soil is likely very deficient in water, so an hour of watering will help.

 

Mine does the same thing. It means not enough watering. If water was not the limiting factor then it wouldn't be greener by the sprinkler heads.

If the PGP ultras and anything like the PGPs, the nozzle is injection molded plastic and get pushed into the popup part. Not really a perfect seal and they "leak" when they are running. Like not one perfect stream coming out the nozzle but maybe a little bit of water coming out the side of the nozzle.

Also, if the grass is tall or the sprinklers don't pop ip high enough, it can sort of block the main stream and cause overwatering (in your case, proper watering) in and around the sprinkler.

Look close when it is running and you should be able to see. I think the solution is to water more.

 

Thanks for your responses. I had been shy about watering due to suspected fungus which I had another thread on. I've since used propiconazole and granular azoxy and I think it's safe to say my yards pretty thirsty. I will get the watering dialed in and move on to the next battle

 

The obvious answer is that your green areas are getting more water than the rest of the yard . (Thanks Captain Obvious!)

I think your sprinkler heads are likely sunk. My system is a little over a year old and I have several that I need to dig up and reset so they spray evenly.