Zone not watering with soil below allowed depletion

I am new to Rachio and this is my first post, but I have read and re-read everything I can find that explains how MAD works, however, I am having a problem understanding everything.

When reading this, please be aware I have my own personal weather station, so all actual rainfall measurements have come from my weather station located on my property.

I have set up all my 13 zones using Flex Daily. Coming from a traditional controller, I originally set it up using the Fixed schedule. Perhaps ironically, two days after I installed the Rachio controller, we had about 10 days of pretty heavy rain. It only watered once using the Fixed schedule, other than testing I did to be sure all my zones were correctly wired and to check to be sure all my heads are working properly (which I do about once a month).

Within day or two of when I set the controller up, I realized it could use the data from my PWS, and I set that up to update pwsweather.

Whist the Rachio (gen 2) was set up on Fixed, and having knowledge from my PWS of the rainfall, the Rachio did not water; rain skip worked great.

And during this rainy period I spent a lot of time reading about the Flex Daily, to which I have changed all my zones. I have configured all the zones with the proper plant, soil, sprinkler head type, etc., and have accepted the default results of these configurations (as shown under Advanced).

However, I have one zone (zone 1) that waters a new podocarpus hedge that is recently planted. It is a drip line, that is, a plastic pipe that has slits or holes in it every so often. The closest type of spray head I see for this is Emitter, which is how I have this zone configured.

Since this is newly planted, it needs more frequent watering until the plants take hold, and I have changed the Allowed Depletion for this zone to 75%, not that this should be the correct setting but to try and see what effect this has on how this zone waters, to try and better understand how all this works.

Currently the soil level moisture for this zone is 55% as of yesterday, and will remain 55% as of the end of today with the predicted rainfall of .07 inch (no rain has fallen so far today).

(Note the Fixed Schedule in the above screen shot is not active.)

As of tomorrow, even with the predicted rainfall of 0.27 inch, the moisture balance will be 70%.

With all this, this zone will not water for the next two weeks when I look at the Soil Moisture graphs, which end on 6/7, but when I look at the zone overview it says Next Run is 6/7 (I thought if no watering was predicted for the next two weeks it should say “Not Scheduled” – perhaps some of your help screens are out of date for the current way this works???)

My question is: why is it not watering this zone when the soil moisture is below 75% today (5/24) and tomorrow (5/25)? Is it because it thinks it might rain the next day, two days from now (5/26) where it is forecasting .88 inches of rain? If that is the case, how far ahead will it look, and how far below the Allowed Depletion will it go before it waters?

If it keeps looking ahead like this, without regard for the soil moisture going below the Allowed Depletion, it will probably never water this time of year because many days for the next two weeks it is forecasting rain.

I used the wrong advanced screen shot…here is the correct one showing 75% allowed depletion.

Increasing the allowed depletion will actually make it water less, you should decrease it to 25% to accomplish what you were trying to do. The number represents how much of the “tank” you want to be depleted before watering. So it won’t water until 75% of the water available to the root zone is depleted if you set it to 75%. The percentage you are seeing in the charts is not the same thing as the allowed depletion. That is how much of the portion you allow to deplete is remaining. So if you set the allowed depletion to 75%, the percentage you see there is how much of of that 75% is remaining in the root zone. It won’t actually water until that is forecasted to reach 0.

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Thank you for your very quick response!

WOW, this is a bit confusing. I think this was discussed in some of the help info I read, but obviously it went by me. I had to read what you wrote several times for it to clock in:

“So if you set the allowed depletion to 75%, the percentage you see there is how much of of that 75% is remaining in the root zone. It won’t actually water until that is forecasted to reach 0.”

Now I realize:

When I see 55% under 5/24 in my soil moisture chart, that has to go to zero before it will water; 0% indicating that I have reached 75% depletion of the water per MAD calculations per my settings under advanced zone settings.

I have changed Allowable Depletion to 25%, and now I see this:

I note the moisture balance is now .49 inch (it was 0.74 inch with this set to 75%), and the percentage is now 108%. So once the balance goes to 0% it will water if I understand correctly. But that will happen sooner since there is less water to deplete?

I still do not understand how the current moisture balance in inches is determined. I did a little test, and tried several different allowable depletion percentages in zone advanced settings. This is what I got:

Allowable Moisture Percentage
Delpetion Balance

10 .19 106
25 .49 108
50 .74 82
75 .74 55
90 .74 45

I think I fully understand the percentage in the soil moisture screen. Again, it is the percent of the water still in the “tank”, and the tank size is determined by the allowable depletion in advanced zone settings. All that water must be used (depleted) before it will water, and if it rains the amount of water in the tank will increase.

But why does the amount of the water (the “Current Moisture Balance”) change as that percentage changes based on the Allowable Depletion percentage in the advanced settings for each zone?

Thanks very much!!!

I have read this article:

It is very technical, and I would have to read it several times, and give it a lot of thought, to understand everything. For now I am going to take it on faith that my Rachio Gen 2 controller is following the advice given in the above referenced document, and will just keep a sharp eye on my landscape to be sure it does not become stressed, as the settings are only going to work out if the soil type and all the other parameters are correct.

I do believe the folks that run Rachio are doing their utmost to give us the best product they can while trying to make something that is very complicated usable by average homeowners and appreciate them and wish them great success.


Thank you for that feedback. Our goal is to try to make scheduling even simpler and not have customers need to understand crop coefficients or evapotranspiration. I want to have “learning” schedules, now that’s a world I want to live in :wink:


So, I thought I understood Allowed Depletion, but when I make changes I am not seeing what I expect.

I have a flower bed I would like to water more frequently than it has been. The zone was configured using the default 50% AD. As of today (7/10) the zone is reporting .12IN 18% Moisture Balance

My expectation is that if I change the AD to 25%, reducing the total amount of allowed reduction in MB by half, my current Moisture Balance would decrease (18% remaining of 1/2 the ‘tank’ would be less than 18% remaining of a quarter ‘tank’). However, when I change the AD to 25%, the MB goes up to .12IN 35%. It seems like the Current MB value is not recalculated based on the new AD, only the % is changed.

So, if I change the AD in the other direction, using 75% AD, the MB is decreasing to 12%, again the opposite of what I would expect, but the MB value in IN has not changed.

Am I missing something?

The moisture balance is a 0-100% scale, 0 being whatever you set AD at, and 100% being, well 100% (technically Rachio goes to 110%). AD is a percentage of field capacity, and adjusting up and down will dictate how much you want the soil to “dry out” between waterings.

There has been a bit of confusion over this on the forums, as people question why MB percentage isn’t a true figure of soil moisture, rather a percentage based on where AD is set.

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Yes, I’ve read through the threads and explanations, and I thought I understood. When I made changes, it behaved in the opposite way I understood it to work, and it doesn’t make sense that the Current Moisture Balance never changes when I change the AD.

If I have a ‘tank’ of 100 and I sent the AD to 50% then I am essentially working with 50 units. If my current balance is 12% of the 50 units that would be 6 units remaining of 50, or 44 used units.
If I adjust the AD to 25%, then I am working with 25 units in my ‘tank’ and because I had used 44 units before, I shouldn’t have any left at this new AD setting, I should be below (at, because we can’t go below 0) the AD level for this new ‘tank’.

Moving forward, the calculations may work once the ‘tank’ is full again, but it seems like a bug that the Current Moisture Balance does not recalculate units after an AD change, and only adjusts the %.

I could force the ‘tank’ empty, but I was really just checking to make sure I wasn’t misunderstanding the way AD works.

Because the physical number is what the true moisture balance is, while the percentage shows is a “sliding scale”, if you will, from what your AD is set to, and the max field capacity.

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OK, but isn’t the percentage going in the wrong direction? I’m a bright guy, I feel so stupid :grinning: