Lawn turning brown

0.2 inch per hour for rotors is very low. You will be applying an excessive amount of water. Some of the soils around Boston are shallow and rocky. Is this your situation?

PGJ are a short radius, low-end rotor. Since they have a 1/2" inlet at bottom you are a candidate to install Hunter Pro Sprays with Hunter MP Rotators. They have different models that throw between 8-35 feet. I believe PGJ rotors only have a two year warranty.

We don’t know if flex daily will work in his case because he can only water three days. I don’t think that flex daily method is compatible with three days a week. His best bet is probably to go with a fixed schedule.

1 Like

no, my soil is 6” loam over clay. i bought a dozen catch cups, so I’ll have some actual nozzle precipitation rates soon. I did read the hunter rotor specs yesterday and you are right about their published rates. I noticed my rotors are a mixture of hunter mp rotors 10’ radius and rain bird regular rotors 30’ radius typically 1.5 rpm nozzles.

1 Like

Good deal. When I lived in Massachusetts, I had rocky soil at one home in the Boston area. But when I moved to Longmeadow in western Mass, I had wonderful loam soil. Smart idea to do a catch cup test. It is fine to mix MP Rotators and gear- drive rotors, since their precipitation rate is similar in inches/hour. Best of luck to you.

I think I would do the fixed watering schedule during the hottest months. We are on permanent odd/even watering restrictions in Oklahoma City, and the flex works great. Occasionally my fescue lawn in the backyard looks stressed, so I add some extra run time.

1 Like

Here’s a great web site that provides an explication of how to perform catch can analysis:

Here’s the result from my catch cans on the back yard zone which ran last night. You can see my estimate of 0.2" was not far off of the actual 0.17". It also shows what a poor job the people who installed my sprinklers did.

1 Like

Wow, this is terrible. What is the spacing on the PGJ rotors? Perhaps a good solution is to replace the rotors with Hunter Pro spray bodies with MP rotators on top. The nozzles come in different models/configurations, throwing anywhere from 8 to 35 feet. Is your system still under warranty? I would contact the sprinkler company and raise cane. If they will not come out, contact the Better Business Bureau.

2 Likes

The system was installed 5 years ago, so not likely to get them back. I should have been more hands on when they installed it. To their defense, our hardscape has changed (patio here, sidewalks there, New house next door), since we were the first house in the subdivision.

I have been tweaking it over the past few years to address blatant issues like burnt sections next to lush green by changing nozzles and adding zones & heads; but digging 50-200 foot trenches by hand kinda stinks. I’m tempted to rip up the old lines then rent one of those machines that trench and bury new lines, but that seems like overkill.

Flex daily would work if Rachio would fix their software. They assume when a zone runs, it waters sufficiently to fill the soil using something like:

Water in soil = Available water X root depth X allowed depletion X nozzle precipitation rate.

this is ONLY TRUE if you don’t change the calculated run times.

If they used a better (and simpler) model:

Water in soil = nozzle precipitation rate X run time

I think the system would work beautifully.

Then switch to fixed schedule, since PR x run time would be basically what you would be calculating…

You obviously have MAJOR issues with your current setup and wildly ranging PR’s, so how is that Rachio’s fault? The beauty in flex daily is the algorithms, as you say, Water in soil = Available water X root depth X allowed depletion X nozzle precipitation rate. This allows the system to adjust according to everything around it.

My yard is looking awesome right now and temps are pushing 110+ and <7% humidity. I have one area in my yard turning brown, and wouldn’t you know it, one of my MP Rotators is spinning out of control and just throwing a fine mist…fixed that last night, and I’ll bet that brown spot will be green within a week…

3 Likes

Not everything!

I want the system to work great in my situation, which is one where I won’t spend $1000’s of dollars on watering my lawn. The fixed schedule is crap! I’ve already got 1.23" of rain today and with the fixed schedule it’s going to water again tomorrow morning, unless I manually tell it to skip.


How can you say this is beautiful? Where is RUN TIME in that equation? You have to agree that the amount of water applied by an irrigation system is controlled by how long the sprinklers run.

Unit time comes from the precipitation rate. The run time is fully derived from the advanced settings.

It is calculating run time based on all the settings you input (Available water X root depth X allowed depletion X nozzle precipitation rate, etc.) in order to “fill” the soil to capacity.

You’ve got MAJOR issues with the uniformity in your system and you want Rachio to overcome those issues?

Fixed schedule is what it is. Hard to say it is crap when it does what it was designed to do…Even with Fixed schedules, you can set them up for rain skip. If you have Rachio pointed to a weather station measuring precipitation, it should skip…

2 Likes

What happens when you go to the schedule and change the duration (because you don’t want to spend $1000’s)? The system breaks and under waters! Should software break because you change a setting?

Haven’t had a need to do that. I’m satisfied how my tree and lawn zones are watering under Flex Daily with no modifications. However I don’t have any restrictions in my watering schedule. If you know what the water duration should be on your limited watering days, fixed is ideal. Use rain and saturation skips. That’s still using the Rachio’s excellent abilities and there’s nothing wrong with a fixed schedule.

2 Likes

But if you do, what will happen? It will break. Can they change the software so it doesn’t break? Yes, by not assuming the duration, but using the actual time.

I don’t get it…you want Rachio to use a calculation you came up with (precipitation rate x run time) to give your grass enough water to green up, complain that it runs too long so you lower the run time, then your grass turns brown, and say Rachio sucks…

You confirmed that Rachio was under watering when you had the zone set up at the wrong PR (1" instead of the real world average of .17). So with the adjustments, it would make sense that Rachio would drastically increase the run time to account for the difference in PR, but you manually forced run time back down because it seemed to high. So the grass is brown and needs more water, but you don’t want to give it more water because you are afraid your bill will be $1000’s. Got it.

4 Likes

No, I don’t want that. I want Rachio to use all the information I have provided to run my sprinklers, including doing the best it can with limited resources.