Flex Daily schedule watering too much

Hi, I think my Flex Daily schedule is overwatering. With my old controller I ran the sprinkler for about 21 hours a week during peak usage in the summer and the yard, with the exception of a few dry spots, stayed green. The Flex Daily schedule setup wants to run about 7 hours every other day. All the extra water has mushrooms growing (in Colorado!) and the grass is growing so quickly that it is difficult to mow. I’m assuming that I don’t have my soils setup correctly but I’m not too sure how to correct them. I re-tested the soil today with the “squeeze test” and I think parts of my yard are clay and parts are clay loam. Currently I have all zones set to to clay loam as I’m not too sure where the dividing lines are. Is there a high level control that allows me to change the settings such that it will only water 80% of the amount that it wants to water? Thanks!

The easiest flex daily lever is just lowering your crop coefficient on your zones 5%-15%. This will tell the system you are burning water (evaporating) slower. It will only affect frequency, not duration. You can look directly at the soil moisture graph to see the predicted two weeks of watering to ensure it is having the right affect. Here is more on adjusting flex daily.


@franz - Thanks! I’ve been looking at it some more, and I think that there are a couple of different things going one. The big one is that I have a hill with sprinklers at the base and in the middle as shown below

The bottom of the hill is getting overwatered. I think this is pattly due to the slope and partly due to the overlap in the zones on the downside of the slope. I adjusted zone 2 only to spray up the hill rather than a full circle. I’ll give that some time to settle in and then play with the crop coefficient if needed.

The other thing that is happening is that I have zones with mixed shade. I’m not too sure what to do about that other than over-water one area or under-water the other. If I want to make adjustments in a scenario like this, would you recommend adjusting the shade settings and hoping to find the right middle ground or going straight to the crop coefficient to control more/less water?

Thanks again!

IMHO shade changes throughout the year. I’d go with crop coefficient.


@jfmoore75, short of manually adjusting the watering time of that zone down, I’m not sure how you can account for any drainage/runoff from zone 1 in this situation…

Also, are you confident that you have your nozzle PR set correctly?

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@franz - Thanks!

@tmcgahey - I adjusted the zone spray, as shown below. It might take some refinement, but hopefully, it will help.

All my zones use rotor heads and have that as their setting. I have not done a cup test. I also think the area of my zones is too small by a factor of 2 - 3, but I’m not too sure how that impacts things. It seems like if that changes the watering times then the number of heads is needed as well…


If you are using the default rotor nozzle in Rachio without adjusting the PR in advanced settings, there could be a fairly large discrepancy. Do you know what model sprinkler bodies you have? We can try to fine tune it a bit, as rotors have huge number of nozzle types with widely different precipitation rates.

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You might want to consider making zone 1 full turn and zone 2 water just the uphill side. The other factor is cutting the time down on the 180 degree zone b/c it will water that area twice as much as it did when it was 360. It would actually be better if you were trying to get 15 minutes of water to do 3 cycles of 5 minutes and have less runoff.

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I agree with @gaustin. Rotors create a whole different set of rules, as PR can change a ton when you have 1/4 vs 1/2 vs full sweep.

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@tmcgahey and @gaustin - thanks for your feedback! To answer the questions I have a mix of Toro and Hunter rotors and a variety of different models. Some are > 10 years old and the cover on the top is ripped off so I’m not sure what they are. Realistically I probably need to do a cup tests to really figure it out but I have so many heads that I’m trying to rely on some defaults and higher level tweaks (like the Crop Coefficient that @franz) suggested.

The point about the PR being incorrect for rotors not doing a full sweep is interesting. I have some zones that are a mix of full and partial sweep but there are others on the perimeter that are all ~1/2 sweep. I wonder if I should double the PR for the perimeter zones?

Lastly, the zone on the hill is specified as such, so I was hoping that the Rachio was automatically taking steps to minimize run off.


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Hi Guys, thanks again for your help. I just got my water bill and I used 15k more gallons that I’ve ever used in the past so I think I’m going to switch to Flex Monthly until I can figure out what’s wrong with my soil settings… Thanks again!

You’ve made some changes (I assume) since you came on here, and that was less than a month ago. Are you sure you don’t want to see where everything works out next month before you change?

@tmcgahey that’s a good point. So far all I’ve changed is the Crop Coefficient. The change has “slowed things down” but it still wants to do 5 - 6 hour runs that history tells me isn’t necessary. In other words, it’s “normal” runs are consistent with how I set things manually in the past but every few days it wants to do a long run that isn’t needed and the extra run time in the long runs adds up. It makes me think that my PR rate isn’t correct and/or my soil definition is incorrect.

So you have it set to flex daily, and it changes the zone run times on its own? Flex daily doesn’t alter the duration of the run (assuming no zone changes made), only frequency.

Do you have watering restrictions where you are, or are you restricting Rachio to only water on certain days?

No watering restrictions or day restrictions on the Rachio. I don’t think the zone run times are changing but due to different crop coefficient / sun exposure settings different zones need water at different times and sometimes it needs to water many zones on the same day. In general it waters less frequently and for much longer than I did manually with my old controller. In theory that sounds like a good thing but, in practice it’s putting down too much water… As I write all of this I wonder if adjusting my watering rates to account for the “half circle” zones would help? Of course getting the water rates is important, I may be overly relying on the high level settings.

Sure. Making sure that your PR’s are correct is crucial to dialing things in…rotor manufacturers typically rate their nozzles at 180 degree sweep, so if you look up the make and model of your rotor nozzles, that part would be easy…

The heads I’ve put on recently have been Hunter PGP-ADJ-B-03 (or whatever size is the default head - it says 1.5 - 4). The Rachio app set Noddle Inches Per Hour to 1 in since I specified rotors. It seems like that is probably ~0.5 in/hr more than I’m putting down. If I corrected that I’d end up with even more water… I have the Crop Coefficient down to 65% on the zones that are clearly getting too much. Maybe I should take that lower.

So with Rotors, you buy them in sets, and you need to mix and match the nozzle based on the arc and radius of the rotor. Every rotor might have a different nozzle if done correctly…but, it is possible that the 1"/hr is higher than what you are putting down, but that will only make things more muddy for you if that is the case…

Here is a good explanation on rotors:

Rotor-type heads aren’t quite as easy. You must select the appropriate nozzle size for each rotor in order to match the precipitation rates. A simple illustration will help explain. Rotor heads move back and forth across the area to be watered. The rotation speed is the same regardless of whether the rotor is adjusted to water a 1/4 circle or a full circle. So the stream from a 1/4 circle head will pass over the same area 4 times in the same amount of time that it takes for a full circle head to make one pass over the area it waters. With the same size nozzle in both, a 1/4 circle rotor will put down 4 times as much water on the area under the pattern as a full circle rotor will. (Remember that after every quarter turn the 1/4 circle rotor reverses direction and covers the same area again!) To match the precipitation rates between these sprinklers, the quarter circle rotor must have a nozzle that puts out 1/4 the amount of water that the full circle nozzle puts out! A half circle rotor must have a nozzle that puts out 1/2 the water of a full circle. This is why when you buy a rotor-type sprinkler head they often include a handful of different size nozzles with it. Wait, there’s more (don’t panic yet, there is a simple solution forthcoming)!

If you have rotors that are adjusted for different radii you will need to adjust the nozzle size to compensate for the radius change also! For example if most of the rotors are set for a 30 foot radius, but one is adjusted down to 20 ft., the 20 ft. one will need a nozzle 1/2 the size. (Remember: when you reduce the RADIUS by 1/3 you reduce the AREA by a little more than half.)