Hunter pgp ultra rotors -- time is wacky

I got rachio at the beginning of this season. Last year I watered 30mins per day every day.

Did you measure your root depth ? If not, it may not be at 6" based on that schedule. How about your soil, where did you get the Loam setting and the 0.17 Available Water number ?

Haven’t measured root depth. Got the loam and the other setting from plainsane who looked it up for me.

So you’re in good shape for the soil settings if you got the numbers from @plainsane. @plainsane , I’m thinking maybe he moves to a 4" root depth, then tries to move deeper over time. It seems unlikely that he’s at 6" right now if he’s been running daily for 30 mins. Maybe MAD should start lower too with a goal to get to 50% over time. What do you think?

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Yea I agree, if the yard is burning drop your roots back to 4 then step it up an inch after 2 watering cycle, keep doing this until you are back to 6.
I wouldn’t move mad, just because it’s effect is already being adjusted by the root change.

You do have shallow roots, we need to get those deeper so it is more drought tolerant but most importantly to extract more nutrients from the frertz you put out.

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Ok. Got the custom Nozzle set up at .35in/hr and root to 4". Flex will be starting st 1am this morning and will run until around noon tomorrow. Gonna sit back and see how it goes. Thanks for you’re help everyone.

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If using published precipitation rates, make sure your zone is set up as defined. For the 0.3"/hr, this would be square watering pattern with 180° arcs, head to head coverage, 45psi. Is this correct? Did not see any info from @Dkd114 about number of heads in the zone, or their arc. Catch cup test would be a more accurate measure of precipitation rate.

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My yard is basically a square. I have 180 degree arches around the perimeter and three zones in the middle that each have three heads spinning 360 degrees. All provide head to head coverage. Each zone has 3 heads in the zone.

Even though this sketch is awful, all do provide head to head coverage and all are hunter pgp ultra rotors. Should settings be different between the center 360s and the outer 180s?

Great diagram! The center 360° would run at 0.15"/hr. Sorry, just added even more run time to your system! Is the distance between the heads 25-30 ft?


Everything looks good, I would just change the precip rate of your center heads to 1/2 the other zones. So .18 for now. Good luck!

My poor well pump. Should I change the blue nozzle on the 360 rotors to something else?

Not sure about changing nozzle, maybe somebody else can chime in.

I think your zones are set up nearly optimally, so I think you can increase your efficiency from 70% to 85-90%. This will save you some watering time. Maybe you can observe how evenly your heads put down water over their throw distance and how much they spray in the wind, then come up with a good value.

Or, better yet, run a catch cup test

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Maybe you can try these nozzles. Get the 180° nozzles and 360° nozzles. They are matched precipitation, so you can run your 360° and 180° heads the same amount of time, and appear to put out about 2x the precipitation rate of your current nozzles. Double check to be sure they fit your rotors, I do not have much experience with Hunter.

Edit: also be sure your system can handle the increased output. You will go from 4.5 gpm on your 360° zones to over 17 gpm.

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@plainsane what do you think about these?

I’ll have to dig in tonight but your 360 rotors should be tossing 4x your 90s and 2x your 180s or you are going to knock your efficient below 50 (rough guesstimate)

The MPR nozzles are a good choice. You just make sure you install quarter, half and full circle nozzles in the appropriate position. If the distributor does not have these nozzles, they can get them free from Hunter. DId you tell us the output of your well in gallons per minute and your pressure? The pipe size, number of heads, nozzle all depend on this critical information. Your well driller should have provided this information.

The most accurate way is to run a zone for 5 minutes and read the water meter.
Then make a custom nozzle for that zone after you do the math for the SF area.

Mine run great!

Great idea but I have a well. No meter.

Next choice is a flow sensor. Or calculate the flow rate from all the sprinklers on one zone.